List of Colorado ballot measures

Elections in Colorado
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Ballot measures List of Colorado ballot measures 1893 2 1972 8 1974 1 1982 1 1992 2 2000 20 2004 36 2006 38 41 42 43 44 E F G H I J K 2008 46 47 48 49 50 51 52 54 58 59 L 2010 62 2012 64 2018 A 2020 B C EE 113 114 2022 125 126 FF 2023 HH II 2024 79 80 I J 127 128 129 131
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El Paso County Local elections 2018
Pueblo Mayoral elections 2023–24
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The U.S. state of Colorado has had a system of direct voting since gaining statehood in 1876. Citizens and the Colorado General Assembly both have the ability to place new legislation, those recently passed by the General Assembly, and constitutional amendments on the ballot for a popular vote. Colorado has three types of ballot measures that can be voted on in a statewide election: initiatives, referendums, and legislatively referred measures. For a measure to be placed on the ballot, supporters must gather signatures from registered voters. From 1877 to 1910, the only ballot measures allowed were legislatively referred measures. In 1910, Referendum 3 was placed on the ballot by the General Assembly and passed, creating a citizen-led process for initiatives and referendums. The first successful citizen-initiated measures were passed in 1912.

Since that time, ballot measures have played a major role in Colorado politics. After Denver was awarded the hosting rights to the 1976 Winter Olympics, citizens moved to block funding the games with a referendum in 1972. A 1990 ballot measure instituting term limits for many elected officials helped galvanize a nationwide movement for term limits, and in 2000 Amendment 20 legalized the medical use of marijuana. That measure was followed by full legalization in 2012 with Amendment 64, and the legalization of psilocybin mushrooms in 2022 with Proposition 122.

The 1876 Constitution of Colorado included procedures for the General Assembly to place measures on the ballot in a statewide election. In the 1890s, a grassroots movement to increase citizen power began, culminating in a special session of the legislature to discuss initiative and referendums in 1910. That session resulted in 1910's Referendum 3, which passed with over 76% of the vote and created a citizen-initiated process.^[1]

Propositions are statutory and amend the Colorado Revised Statutes, whereas amendments change the state constitution. From 1877 to 2016, constitutional amendments, like propositions, required only a simple majority to pass. Following the passage of Amendment 71 in 2016, amendments require 55% of the vote to pass, unless the amendment is to remove language from the constitution.^[2][3][4] Referred propositions and amendments are lettered, whereas citizen initiatives are numbered.^[5]

In 2020, as part of his administration's response to the COVID-19 pandemic, Governor Jared Polis issued an emergency rule allowing petition signature gatherers to do so via email and mail, rather than in-person efforts. The change, while upheld by the Denver District Court, was overturned by the Colorado Supreme Court later that year.^[6]

After the 1876 Constitution was adopted, a legislatively referred constitutional amendment that would have granted women the right to vote was placed on the ballot for the 1877 election.^[7]: 92 The measure failed, with over two-thirds of voters against it.^[8] Henry Blackwell, a founder of the American Woman Suffrage Association, summed up the unsuccessful campaign by saying "Woman Suffrage can never be carried by a popular vote without a political party behind it".^[9] Blackwell was proven correct in 1893 when, in part due to gains made by the Colorado People's Party in the General Assembly, voters supported a women's suffrage ballot measure by a 55%–45% margin.^{[10][7]: 124–158}

In 1970, the International Olympic Committee granted Denver hosting rights for the 1976 Winter Olympics.^[11] Governor John Love claimed that the games would cost taxpayers only $5,000,000. Activists quickly noted a wide variety of issues with the state's cost estimate, however, including a lack of transportation infrastructure, no planning for the Olympic Village, and issues with planned events sites.^[12] A petition for 1972's Measure 8 quickly reached the necessary 51,000 signatures and 60% of Coloradans voted to prohibit the state from funding the Olympics. Later estimates found that the cost for Denver to host the games would have been $92,000,000, over 18 times the state's estimate.^[13] Richard Lamm, who was a leader in the local anti-Olympics movement, would later parlay his fame from the measure into three terms as Governor.^[14]

The 1984 ballot included Amendment 3, which barred the use of state funds for abortion services. The measure passed by less than one percentage point and gave Colorado the distinction of being both the first state to decriminalize abortion, having done so in 1967, and the first state to prohibit the government from funding it.^[15] 1990's Amendment 5 has been credited by the Initiative & Referendum Institute as having started the term limits movement in the United States and was followed by similar initiatives in 1994 and 1996. Colorado's efforts were unique because they placed term limits on members of Congress in addition to state-level officials.^[1] The term-limits movement resulted in the Supreme Court case U.S. Term Limits, Inc. v. Thornton (1995), which determined that states could not place restrictions on congresspeople beyond the constitutional requirements.^[16][17]

In 2000, Amendment 20 passed with 54% of the vote and legalized the medical use of marijuana in the state.^[18] It was followed by 2012's Amendment 64, which passed by similar margins and legalized the recreational use of marijuana.^[19] The Economist described the vote as "an electoral first not only for America but for the world."^[20] Colorado continued this trend of loosening drug policy in 2022 when voters passed Proposition 122 and legalized the use of psilocybin mushrooms in designated "healing centers".^[21]

The Constitution of Colorado grants citizens some initiative and referendum powers in Article V. In order for a measure to be placed on the ballot, a petition must receive signatures equal to 5% of the votes cast in the previous election. The governor's veto power does not extend to citizen-initiated measures, which go into effect within one month of election returns being certified.^[22][23]

• Initiatives create new state statutes or constitutional amendments. They may be placed on the ballot if their petition is filed at least three months before the upcoming election.^[23]
• Referendums repeal legislation passed in the previous General Assembly session. They may be placed on the ballot if their petition is filed at least 90 days after the previous General Assembly session adjourns.^[22]

At the General Assembly's discretion, the legislature may place additional measures on the ballot. Article XIX of the Constitution requires that constitutional amendments passed by the legislature be voted on in the next general election.^[22] The General Assembly can also vote to place statute changes and proposed spending on the general election ballot.^[24]

Ballot Measures from 1877

Measure name	Description[8]	Status[8]	Yes votes	No votes
Referendum 1	A constitutional amendment granting women the right to vote	Failed	6,612 (32.00%)	14,053 (68.00%)

Ballot Measures from 1880

Measure name	Description[25]	Status[25]	Yes votes	No votes
Amendment 1	A constitutional amendment requiring uniform taxation	Passed	19,198 (84.80%)	3,436 (15.20%)

Ballot Measures from 1881

Measure name	Description[26]	Status[26]	Yes votes	No votes
State Capital Referendum	A referendum on whether the permanent location of the state capital should be Denver or some other location[a]	Passed[b]	30,248 (66.48%)	15,249 (33.52%)

Ballot Measures from 1882

Measure name	Description[25]	Status[25]	Yes votes	No votes
Amendment 2	A constitutional amendment establishing salaries for some state officials	Passed	32,858 (79.00%)	8,738 (21.00%)

Ballot Measures from 1884

Measure name	Description[25]	Status[25]	Yes votes	No votes
Amendment 3(a)	A constitutional amendment modifying some General Assembly procedures	Passed	47,020 (88.00%)	6,413 (12.00%)
Amendment 3(b)	A constitutional amendment modifying some General Assembly procedures	Passed	45,080 (87.90%)	6,188 (12.10%)
Amendment 3(c)	A constitutional amendment modifying some General Assembly procedures	Passed	45,394 (88.00%)	6,180 (12.00%)

Ballot Measures from 1886

Measure name	Description[25]	Status[25]	Yes votes	No votes
Amendment 4	A constitutional amendment vesting judicial power in the state court system	Passed	17,068 (63.90%)	9,629 (36.10%)
Amendment 5	A constitutional amendment relating to "original jurisdiction"	Passed	16,897 (64.10%)	9,453 (35.90%)
Amendment 6	A constitutional amendment providing for additional judges on the Colorado Supreme Court	Failed	6,478 (30.00%)	15,132 (70.00%)
Amendment 7	A constitutional amendment allowing the General Assembly to establish criminal courts	Failed	7,549 (29.00%)	18,512 (71.00%)
Amendment 8	A constitutional amendment allowing the General Assembly to create police magistrates	Failed	7,148 (27.80%)	18,553 (72.20%)
Amendment 9	A constitutional amendment relating to judges on Colorado district courts	Passed	14,938 (57.90%)	10,867 (42.10%)
Amendment 10	A constitutional amendment allowing the General Assembly to modify the state court system	Passed	14,568 (51.00%)	14,022 (49.00%)

Ballot Measures from 1887

Measure name	Description[25]	Status[25]	Yes votes	No votes
Measure 1	A constitutional amendment relating to the public debt	Passed	--	--

Ballot Measures from 1888

Measure name	Description[25]	Status[25]	Yes votes	No votes
Measure 1	A constitutional amendment limiting the reasons to contract public debt	Passed	15,212 (53.20%)	13,385 (46.80%)
Measure 2	A constitutional amendment raising property taxes	Failed	749 (7.90%)	8,778 (92.10%)
Measure 3	A constitutional amendment limiting the reasons to contract public debt	Passed	13,921 (51.30%)	13,209 (48.70%)
Measure 4	A constitutional amendment limiting the reasons to contract public debt	Passed	--	--

Ballot Measures from 1890

Measure name	Description[25]	Status[25]	Yes votes	No votes
Measure 1	A constitutional amendment modifying the size and salaries of the Colorado Supreme Court	Failed	15,283 (42.10%)	20,991 (57.90%)
Measure 2	A constitutional amendment relating to "compensation and services"	Failed	15,395 (43.40%)	20,078 (56.60%)

Ballot Measures from 1892

Measure name	Description[25]	Status[25]	Yes votes	No votes
Measure 1	A constitutional amendment relating to uniform taxation	Passed	13,713 (52.70%)	12,294 (47.30%)
Measure 3	A constitutional amendment relating to the maximum tax rate	Passed	12,440 (51.50%)	11,731 (48.50%)

Ballot Measures from 1893

Measure name	Description[25]	Status[7]	Yes votes	No votes
Measure 2	A constitutional amendment granting women the right to vote[c]	Passed	35,798 (54.90%)	29,451 (45.10%)

Ballot Measures from 1894

Measure name	Description[25]	Status[25]	Yes votes	No votes
Measure 1	A constitutional amendment relating to locality's "pledging of credit"	Failed	26,434 (33.80%)	51,711 (66.20%)
Measure 2	A constitutional amendment relating to limits on state debt	Failed	22,393 (29.50%)	53,634 (70.50%)
Measure 3	A constitutional amendment relating to city debt	Failed	21,293 (29.70%)	50,513 (70.30%)

Ballot Measures from 1896

Measure name	Description[25]	Status[25]	Yes votes	No votes
Measure 1	A constitutional amendment relating to limits on state debt	Failed	25,340 (38.90%)	39,790 (61.10%)

Ballot Measures from 1900

Measure name	Description[25]	Status[25]	Yes votes	No votes
Measure 1	A constitutional amendment relating to the process to amend the constitution	Passed	31,471 (73.10%)	11,568 (26.90)

Ballot Measures from 1902

Measure name	Description[25]	Status[25]	Yes votes	No votes
Measure 1	A constitutional amendment relating to the election process for county commissioners	Passed	49,646 (65.10%)	26,559 (34.90%)
Measure 2	A constitutional amendment relating to the city and county of Denver	Passed	59,750 (69.90%)	25,767 (30.1%)
Measure 3	A constitutional amendment relating to the eight-hour work day[27]	Passed	72,980 (73.50%)	26,266 (26.50%)
Measure 4	A constitutional amendment relating to voter qualifications	Passed	44,769 (62.30%)	27,077 (37.70%)
Measure 5	A constitutional amendment relating to the election process for district attorneys	Passed	45,191 (64.20%)	25,243 (35.80%)
Measure 6	A constitutional amendment relating to property tax exemptions	Failed	32,710 (31.10%)	72,370 (68.90%)
Measure 7	A constitutional amendment relating to tax limits	Failed	31,527 (31.10%)	69,741 (68.90%)
Measure 8	A constitutional amendment relating to the election process for justices of the peace	Passed	48,682 (65.10%)	26,082 (34.90%)
Measure 9	A constitutional amendment relating to the election process for county officials	Passed	48,944 (65.20%)	26,140 (34.80%)
Measure 10	A constitutional amendment relating to the election process for county judges	Passed	44,856 (63.90%)	25,326 (36.10%)

Ballot Measures from 1904

Measure name	Description[25]	Status[25]	Yes votes	No votes
Measure 1	A constitutional amendment relating to exemptions to uniform taxation	Passed	42,696 (80.30%)	10,444 (19.70%)
Measure 2	A constitutional amendment relating to the Colorado Supreme Court	Passed	5,863 (56.40%)	4,528 (43.60%)
Measure 3	A constitutional amendment relating to the Colorado Supreme Court	Passed	5,006 (54.50%)	4,174 (45.50%)
Measure 4	A constitutional amendment relating to the Colorado Supreme Court	Passed	5,389 (55.70%)	4,293 (44.30%)
Measure 5	A constitutional amendment relating to the Colorado Supreme Court	Passed	5,264 (55.50%)	4,218 (44.50%)

Ballot Measures from 1906

Measure name	Description[25]	Status[25]	Yes votes	No votes
Measure 1	A constitutional amendment relating to the election process and voting machines	Passed	27,460 (72.40%)	10,467 (27.60%)

Ballot Measures from 1908

Measure name	Description[25]	Status[28]	Yes votes	No votes
Referendum 1	A constitutional amendment allowing the state to issue bonds for the purpose of paying outstanding warrants	Failed	26,254 (48.98%)	27,352 (51.02%)
Referendum 2	A constitutional amendment modifying the salaries of state officials and judges	Failed	16,088 (29.88%)	37,753 (70.12%)
Referendum 3	A constitutional amendment modifying the salaries of county officials	Failed	18,558 (39.00%)	29,022 (61.00%)

Ballot Measures from 1910

Measure name	Description[25]	Status[29]	Yes votes	No votes
Referendum 1	A constitutional amendment allowing the state to issue bonds for the purpose of paying outstanding warrants	Passed	40,054 (50.39%)	39,441 (49.61%)
Referendum 2	A constitutional amendment modifying the Colorado Board of Land Commissioners	Passed	42,128 (66.42%)	21,300 (33.58%)
Referendum 3	A constitutional amendment creating an initiative and referendum process in the state	Passed	89,141 (76.95%)	26,698 (23.05%)
Referendum 4	A constitutional amendment modifying the salaries of state legislators	Passed	39,245 (55.83%)	31,047 (44.17%)
Referendum 5	A constitutional amendment relating to higher education institutions	Passed	59,295 (79.70%)	15,105 (20.30%)

Ballot Measures from 1912

Measure name	Description[25]	Status[30]	Yes votes	No votes
Measure 1	A constitutional amendment prohibiting alcoholic beverages statewide	Failed	75,877 (39.39%)	116,774 (60.61%)
Measure 2	An initiative allowing search and seizure to enforce prohibition laws	Failed	64,616 (44.93%)	79,190 (55.07%)
Measure 3	An initiative creating an eight-hour workday for female employees	Passed	108,959 (77.29%)	32,019 (22.71%)
Measure 4	An initiative establishing regulations for public service corporations	Failed	30,347 (32.12%)	64,138 (67.88%)
Measure 5	An initiative establishing a Colorado State Fair	Failed	49,102 (48.35%)	52,462 (51.65%)
Measure 6	A constitutional amendment allocating funds for the Colorado Immigration Bureau	Failed	30,359 (35.87%)	54,272 (64.13%)
Measure 7	An initiative introducing cost-saving measures for publicizing future ballot measures	Failed	39,551 (43.85%)	50,635 (56.15%)
Measure 8	A constitutional amendment allowing home rule for counties	Passed	49,596 (52.55%)	44,778 (47.45%)
Measure 9	A constitutional amendment establishing a recall process for elected officials	Passed	53,620 (57.54%)	39,564 (42.46%)
Measure 10	An initiative modifying election laws	Failed	37,616 (49.40%)	38,537 (50.60%)
Measure 11	An initiative establishing a special election system for ballot measures	Failed	33,413 (45.12%)	40,634 (54.88%)
Measure 12	A constitutional amendment establishing a definition for "contempt of court" and allowing for jury trials for such charges	Failed	31,850 (43.21%)	41,855 (56.79%)
Measure 13	A constitutional amendment establishing a public utilities court with exclusive power over rates	Failed	27,534 (34.70%)	51,820 (65.30%)
Measure 14	An initiative providing for a "headless ballot" to be used in elections	Passed	43,390 (52.34%)	39,504 (47.66%)
Measure 15	A constitutional amendment extending wider control of schools to the public	Failed	38,318 (40.76%)	55,691 (59.24%)
Measure 16	A constitutional amendment establishing juvenile courts in localities with populations greater than 100,000 people	Passed	55,416 (57.54%)	40,891 (42.46%)
Measure 17	An initiative to allocate some public aid to supporting the children of single mothers	Passed	82,337 (68.50%)	37,870 (31.50%)
Measure 18	An initiative modifying the laws relating to civil service	Passed	38,426 (52.13%)	35,282 (47.87%)
Measure 19	An initiative establishing an eight-hour workday for people working in underground mines, smelters, mills, and coke ovens	Passed	52,525 (51.85%)	48,777 (48.15%)
Measure 20	An initiative allocating control of some funds to the Colorado Highway Commission	Failed	44,568 (49.70%)	45,101 (50.30%)
Measure 21	A referendum to uphold a law requiring teacher examinations	Failed	25,369 (31.93%)	54,086 (68.07%)
Measure 22	A referendum upholding a law modifying water rights relating to irrigation	Failed	22,931 (32.51%)	47,614 (67.49%)
Measure 23	A referendum upholding a law which altered the rules surrounding the branding of livestock	Failed	37,387 (49.77%)	337,740 (50.23%)
Measure 24	A constitutional amendment replacing the Colorado Board of Equalization with the Colorado Tax Commission	Failed	32,548 (44.86%)	40,012 (55.14%)
Measure 25	A referendum upholding a law which established an eight-hour workday for people working in underground mines, smelters, and coke ovens	Passed	69,489 (69.16%)	30,992 (30.84%)
Measure 26	A referendum upholding a law requiring teachers to attend summer trainings	Failed	23,521 (27.10%)	63,266 (72.90%)
Measure 27	A constitutional amendment allowing county officials to be paid from outside sources	Failed	28,889 (40.97%)	41,622 (59.03%)
Measure 28	A constitutional amendment raising the limitation on county debts	Failed	29,741 (38.61%)	47,284 (61.39%)
Measure 29	A referendum upholding a law which changed some rules related to the management of public funds	Failed	20,968 (32.12%)	44,322 (67.88%)
Measure 30	A constitutional amendment defining mining and smelting as public interests	Failed	35,997 (48.68%)	37,953 (51.32%)
Measure 31	A constitutional amendment allowing the state to issue bonds for the purpose of funding state highways	Failed	36,636 (40.72%)	53,327 (59.28%)
Measure 32	An initiative authorizing the construction of a tunnel through James Peak	Failed	45,800 (32.95%)	93,183 (67.05%)

Ballot Measures from 1914

Measure name	Description[25]	Status[31]	Yes votes	No votes
Measure 1	A constitutional amendment requiring that rejected measures not be placed on the ballot again until six years have passed	Failed	55,667 (33.09%)	112,537 (66.91%)
Measure 2	A constitutional amendment prohibiting alcohol	Passed	129,589 (52.30%)	118,176 (47.70%)
Measure 3	A constitutional amendment allowing women to serve as jurors and requiring 3/4 of jurors to agree for a verdict to be reached	Failed	67,130 (46.42%)	77,488 (53.58%)
Measure 4	A constitutional amendment creating a process by which citizens could petition for a special election solely for ballot measures	Failed	40,643 (33.42%)	80,977 (66.58%)
Measure 5	An initiative to codify some laws relating to women and children	Failed	68,242 (48.62%)	72,122 (51.38%)
Measure 6	An initiative providing for probation in criminal cases involving minors and first offenders	Failed	62,561 (47.73%)	68,512 (52.27%)
Measure 7	An initiative increasing the state roads fund for the purpose of constructing new highways	Passed	117,146 (68.51%)	53,844 (31.49%)
Measure 8	A constitutional amendment defining newspapers as public utilities	Failed	35,752 (28.11%)	91,426 (71.89%)
Measure 9	A referendum upholding a law relating to the capitalization of public utilities	Failed	37,633 (37.20%)	63,603 (62.80%)
Measure 10	A referendum upholding a law relating to the licensing and regulation of commission merchants	Failed	39,448 (36.90%)	67,454 (63.10%)
Measure 11	A referendum upholding a law relieving employees from assuming risk of injury or death	Passed	69,006 (53.37%)	60,298 (46.63%)
Measure 12	A referendum upholding a law which altered the peace officer appointment process	Failed	49,116 (42.36%)	66,836 (57.64%)
Measure 13	A referendum upholding a law relating to a public utilities commission	Failed	39,703 (37.85%)	65,182 (62.15%)
Measure 14	A constitutional amendment allowing localities sixty years to make up for any indebtedness	Failed	38,589 (37.18%)	65,206 (62.82%)
Measure 15	A constitutional amendment relating to the equalization of tax assessments	Passed	55,987 (50.32%)	55,275 (49.68%)
Measure 16	An initiative introducing cost-saving measures for publicizing future ballot measures	Failed	48,301 (46.19%)	56,259 (53.81%)

Ballot Measures from 1916

Measure name	Description[25]	Status[32]	Yes votes	No votes
Measure 1	A referendum upholding a law relating to medical practice regulation	Passed	96,879 (54.06%)	82,317 (45.94%)
Measure 2	A constitutional amendment to codify the state civil service	Failed	62,458 (39.28%)	96,561 (60.72%)
Measure 3	A constitutional amendment exempting beer from existing prohibitions on alcohol	Failed	77,345 (32.16%)	163,134 (67.84%)
Measure 4	An initiative establishing treatment procedures for people with mental illnesses	Passed	164,220 (80.64%)	39,415 (19.36%)
Measure 5	An initiative abolishing the Colorado Tax Commission and transferring its duties to the Colorado Board of Equalization	Failed	80,362 (48.89%)	84,011 (51.11%)
Measure 6	An initiative relating to the regulation of livestock running	Failed	85,279 (35.47%)	155,134 (64.53%)
Measure 7	An initiative allowing for the investment of public school funds	Passed	102,956 (60.92%)	66,058 (39.08%)
Measure 8	An measure calling for a constitutional convention	Failed	53,530 (43.48%)	69,579 (56.52%)

Ballot Measures from 1918

Measure name	Description[25]	Status[33]	Yes votes	No votes
Measure 1	An initiative providing public aid for blind adults	Passed	131,469 (93.30%)	9,440 (6.70%)
Measure 2	A constitutional amendment codifying the state civil service	Passed	75,301 (64.59%)	41,287 (35.41%)
Measure 3	An initiative strengthening existing alcohol prohibition	Passed	113,636 (63.71%)	64,740 (36.29%)
Measure 4	A constitutional amendment limiting the time for state legislators to introduce bills from 25 days to 15 days	Passed	67,693 (77.28%)	19,901 (22.72%)
Measure 5	A constitutional amendment relating to the publication of ballot measures before the election	Passed	98,715 (88.97%)	12,237 (11.03%)

Ballot Measures from 1920

Measure name	Description[25]	Status[34]	Yes votes	No votes
Measure 1	An initiative establishing fixed hours for city fire department employees	Passed	113,140 (57.80%)	82,596 (42.20%)
Measure 2	An initiative requiring the licensing and regulation of chiropractors	Failed	84,286 (43.52%)	109,385 (56.48%)
Measure 3	An initiative creating a county called Limon County	Failed	34,881 (19.81%)	141,239 (80.19%)
Measure 4	An initiative creating a county called Flagler County	Failed	33,295 (19.17%)	140,363 (80.83%)
Measure 5	A constitutional amendment allowing the state to issue bonds for the purpose of building the Moffat, Monarch, and San Juan Tunnels	Failed	101,841 (44.68%)	126,099 (55.32%)
Measure 6	An initiative allocating $350,000 for the creation of a Psychopathic Hospital and Laboratory (equivalent to $5,323,256 in 2023)	Passed	155,049 (75.51%)	50,295 (24.49%)
Measure 7	A constitutional amendment creating a property tax for the purpose of funding state educational facilities	Passed	160,268 (75.39%)	52,324 (24.61%)
Measure 8	A constitutional amendment authorizing the state to issue a $5,000,000 bond for the purpose of constructing new highways (equivalent to $76,046,512 in 2023)	Passed	100,130 (58.51%)	70,997 (41.49%)
Measure 9	A constitutional amendment increasing the number of county judges	Failed	35,095 (26.49%)	97,398 (73.51%)
Measure 10	A constitutional amendment increasing the salaries of constitutional offices and judges	Failed	49,313 (30.40%)	112,878 (69.60%)

Ballot Measures from 1922

Measure name	Description[25]	Status[35]	Yes votes	No votes
Measure 1	A constitutional amendment allowing the state to issue $1,500,000 in bonds for the purpose of constructing new highways (equivalent to $27,304,175 in 2023)	Passed	131,271 (66.36%)	66,536 (33.64%)
Measure 2	A constitutional amendment creating a public utilities commission	Failed	75,061 (41.08%)	107,655 (58.92%)
Measure 3	An initiative reapportioning seats in the Colorado General Assembly	Failed	61,502 (37.72%)	101,537 (62.28%)
Measure 4	A constitutional amendment allowing the legislature to issue some exemptions from the ad valorem tax and create an income tax	Failed	42,466 (26.08%)	120,355 (73.92%)
Measure 5	An initiative relating to experimental operations on humans and animals	Failed	35,476 (16.61%)	178,120 (83.39%)
Measure 6	A measure calling for a constitutional convention	Failed	53,015 (36.29%)	93,081 (63.71%)
Measure 7	A constitutional amendment relating to the location and control of higher education institutions	Passed	87,282 (59.95%)	58,315 (40.05%)
Measure 8	A constitutional amendment establishing four-year terms for some county officials	Failed	37,945 (26.40%)	105,782 (73.60%)
Measure 9	A constitutional amendment establishing four-year terms for some state officials	Failed	40,081 (28.54%)	100,367 (71.46%)
Measure 10	A constitutional amendment allowing the legislature to grant non-citizens the ability to own property	Failed	43,074 (31.15%)	95,219 (68.85%)

Ballot Measures from 1924

Measure name	Description[25]	Status[36]	Yes votes	No votes
Measure 1	A constitutional amendment establishing a state printer and a printing building committee	Failed	32,150 (12.48%)	225,505 (87.52%)
Measure 2	A constitutional amendment authorizing the state to issue bonds for the purpose of paying bonuses to military members	Failed	91,510 (43.35%)	119,586 (56.65%)
Measure 3	A constitutional amendment allowing the legislature to set salaries for state officials	Failed	67,230 (34.20%)	129,344 (65.80%)

Ballot Measures from 1926

Measure name	Description[25]	Status[37]	Yes votes	No votes
Measure 1	A constitutional amendment allowing the General Assembly to set salaries for state officials and judges	Failed	95,625 (47.73%)	104,709 (52.27%)
Measure 2	A constitutional amendment allowing the General Assembly to set salaries for county officials	Failed	60,086 (33.69%)	118,284 (66.31%)
Measure 3	A constitutional amendment allowing the legislature to modify vehicle registration fees	Failed	68,459 (33.77%)	134,292 (66.23%)
Measure 5	A constitutional amendment allowing the General Assembly to regulate alcohol	Failed	107,749 (41.06%)	154,672 (58.94%)
Measure 6	An initiative allowing dentists licensed in other states to practice in Colorado	Failed	56,433 (23.59%)	182,816 (76.41%)
Measure 7	A constitutional amendment creating a public utilities commission	Failed	35,137 (17.88%)	161,372 (82.12%)
Measure 8	An initiative creating a fuel tax and vehicle registration fees and mandating that all revenues be used exclusively for roads	Failed	81,762 (35.98%)	145,482 (64.02%)

Ballot Measures from 1928

Measure name	Description[25]	Status[38]	Yes votes	No votes
Measure 1	A constitutional amendment allowing the General Assembly to set salaries for state officials and judges	Passed	134,724 (53.09%)	119,060 (46.91%)
Measure 2	A constitutional amendment requiring that voters on issues related to school funding be property tax payers	Failed	69,005 (30.80%)	155,018 (69.20%)
Measure 3	A constitutional amendment modifying eminent domain rules	Failed	32,294 (16.97%)	157,973 (83.03%)
Measure 4	A constitutional amendment authorizing the state to issue $60,000,000 in bonds for the purpose of constructing new highways (equivalent to $1,064,651,163 in 2023)	Failed	82,422 (32.16%)	173,881 (67.84%)
Measure 5	A constitutional amendment creating an elected Board of Education	Failed	84,416 (34.84%)	157,889 (65.16%)

Ballot Measures from 1930

Measure name	Description[25]	Status[39]	Yes votes	No votes
Measure 1	A measure calling for a constitutional convention	Failed	93,879 (48.97%)	97,826 (51.03%)
Measure 2	A constitutional amendment creating an elected Board of Education	Failed	70,643 (32.05%)	149,770 (67.95%)

Ballot Measures from 1932

Measure name	Description[25]	Status[40]	Yes votes	No votes
Measure 1	A constitutional amendment making some county positions hold a four-year term	Failed	102,117 (37.57%)	169,703 (62.43%)
Measure 2	A referendum upholding a law which increased the oleomargarine tax from 10 cents to 15 cents a pound	Failed	134,313 (38.16%)	217,671 (61.84%)
Measure 3	An initiative reapportioning seats in the Colorado General Assembly	Passed	162,871 (53.07%)	144,037 (46.93%)
Measure 4	A constitutional amendment allowing the General Assembly to create a graduated income tax	Failed	85,573 (27.49%)	225,713 (72.51%)
Measure 5	A constitutional amendment allowing the General Assembly to create a limited income tax	Failed	101,438 (32.11%)	214,464 (67.89%)
Measure 6	A constitutional amendment limiting fuel taxes	Failed	124,610 (33.37%)	248,801 (66.63%)
Measure 7	A constitutional amendment repealing the statewide alcohol prohibition	Passed	233,311 (56.07%)	182,771 (43.93%)

Ballot Measures from 1934

Measure name	Description[25]	Status[41]	Yes votes	No votes
Measure 1	A constitutional amendment centralizing most authority with the Governor of Colorado	Failed	102,117 (37.57%)	169,703 (62.43%)
Measure 2	A constitutional amendment relating to civil service reform	Failed	60,745 (24.02%)	192,140 (75.98%)
Measure 3	A constitutional amendment eliminating uniform taxation	Failed	107,457 (39.98%)	161,952 (60.11%)
Measure 4	A constitutional amendment granting voters authority to approve new taxes	Failed	126,649 (45.93%)	149,098 (54.07%)
Measure 5	A constitutional amendment requiring that taxes related to gasoline and vehicles be allocated exclusively for roads	Passed	160,482 (54.68%)	132,994 (45.32%)
Measure 6	A constitutional amendment limiting fuel taxes to 3 cents	Failed	87,090 (31.69%)	187,720 (68.31%)
Measure 7	An initiative to requiring chain stores to pay license fees	Passed	197,144 (55.80%)	156,147 (44.20%)

Ballot Measures from 1936

Measure name	Description[25]	Status[42]	Yes votes	No votes
Measure 1	A constitutional amendment establishing an ownership tax on motor vehicles	Passed	218,795 (66.90%)	108,270 (33.10%)
Measure 2	An initiative providing public assistance to sufferers of tuberculosis below a certain income level	Passed	176,872 (56.98%)	133,516 (43.02%)
Measure 3	A constitutional amendment limiting tax rates based on the size of a town	Failed	60,228 (17.52%)	283,583 (82.48%)
Measure 4	A constitutional amendment allowing the General Assembly to establish an income tax	Failed	67,155 (20.40%)	262,022 (79.60%)
Measure 5	A constitutional amendment providing a pension of $45 a month to the elderly (equivalent to $988 in 2023)	Passed	239,289 (64.04%)	134,377 (35.96%)
Measure 6	An initiative modifying the laws relating to worker's compensation	Passed	203,195 (63.91%)	114,733 (36.09%)
Measure 7	A constitutional amendment allowing women to serve on juries	Failed	129,872 (41.35%)	184,204 (58.65%)
Measure 8	A constitutional amendment allowing the general assembly to establish a graduated income tax	Passed	167,268 (51.24%)	159,143 (48.76%)
Measure 9	A constitutional amendment exempting churches, schools, and cemeteries from property tax	Passed	227,254 (67.16%)	111,123 (32.84%)

Ballot Measures from 1938

Measure name	Description[25]	Status[25]	Yes votes	No votes
Measure 1	A constitutional amendment giving healthcare practitioners the authority to self-regulate	Failed	94,846 (23.13%)	315,174 (76.87%)
Measure 2	A constitutional amendment repealing the $45 a month pension and granting the legislature authority to set pensions	Failed	157,975 (36.52%)	274,598 (63.48%)
Measure 3	An initiative repealing the license fees for chain stores	Failed	167,109 (38.70%)	264,700 (61.30%)

Ballot Measures from 1940

Measure name	Description[25]	Status[43]	Yes votes	No votes
Measure 1	A constitutional amendment establishing property tax on all intangible property	Failed	50,806 (10.35%)	440,202 (89.65%)
Measure 2	An initiative to establish a racing commission to oversee horse and dog racing	Failed	203,195 (42.28%)	277,392 (57.72%)
Measure 3	A constitutional amendment establishing a game and fish commission	Failed	196,907 (41.92%)	272,768 (58.08%)
Measure 4	A constitutional amendment modifying the General Assembly's ability relating to income taxes	Failed	81,787 (18.26%)	366,049 (81.74%)
Measure 5	A constitutional amendment lowering the elderly's pension to $30 a month (equivalent to $652 in 2023)	Failed	138,383 (27.85%)	358,582 (72.15%)

Ballot Measures from 1942

Measure name	Description[25]	Status[44]	Yes votes	No votes
Measure 1	A constitutional amendment limiting the session length of General Assembly meetings	Failed	72,147 (49.49%)	73,648 (50.51%)

Ballot Measures from 1944

Measure name	Description[25]	Status[45]	Yes votes	No votes
Measure 1	A constitutional amendment allowing women to serve on juries	Passed	195,793 (60.65%)	127,057 (39.35%)
Measure 2	A constitutional amendment allowing some foreigners the ability to purchase property	Failed	173,652 (47.01%)	195,752 (52.99%)
Measure 3	An initiative appropriating $1,500,000 in funding for old age pensions (equivalent to $25,962,193 in 2023)	Passed	195,793 (60.65%)	127,057 (39.35%)
Measure 4	A constitutional amendment granting veterans and their widows preference in the civil service	Passed	256,563 (70.55%)	107,100 (29.45%)

Ballot Measures from 1946

Measure name	Description[25]	Status[46]	Yes votes	No votes
Measure 1	A constitutional amendment allowing for secret ballots	Passed	118,470 (56.23%)	92,203 (43.77%)
Measure 2	A constitutional amendment requiring that any balance in the state pension fund roll-over each year	Failed	96,787 (36.38%)	169,243 (63.62%)

Ballot Measures from 1948

Measure name	Description[25]	Status[47]	Yes votes	No votes
Measure 1	A constitutional amendment reorganizing the Colorado Department of Education	Passed	238,100 (65.03%)	128,054 (34.97%)
Measure 2	An initiative establishing regulations for animal racing	Passed	238,371 (56.50%)	183,292 (43.50%)
Measure 3	A constitutional amendment allowing localities to prohibit alcohol	Failed	334,331 (73.46%)	120,799 (26.54%)
Measure 4	A constitutional amendment increasing the old age pension to $55 a month (equivalent to $697 in 2023)	Failed	120,799 (26.54%)	334,331 (73.46%)

Ballot Measures from 1950

Measure name	Description[25]	Status[48]	Yes votes	No votes
Measure 1	A constitutional amendment modifying home rule for some localities	Passed	145,780 (61.39%)	91,700 (38.61%)
Measure 2	A constitutional amendment modifying some rules relating to the General Assembly	Passed	134,048 (58.09%)	96,709 (41.91%)
Measure 3	A constitutional amendment exempting some members of executive departments from the civil service	Failed	103,848 (33.26%)	208,408 (66.74%)

Ballot Measures from 1952

Measure name	Description[25]	Status[49]	Yes votes	No votes
Measure 1	A constitutional amendment modifying salaries and retirement procedures for judges	Passed	223,365 (58.28%)	159,883 (41.72%)
Measure 2	A constitutional amendment modifying public utilities regulations	Failed	173,652 (46.01%)	203,732 (53.99%)
Measure 3	A constitutional amendment exempting some forms of property from tax	Failed	96,584 (25.67%)	279,682 (74.33%)
Measure 4	A constitutional amendment creating a severance tax on some gasoline products	Failed	177,125 (35.96%)	315,392 (64.04%)
Measure 5	An initiative prohibiting firefighters from working more than 60 hours a week	Failed	169,126 (38.84%)	266,275 (61.16%)
Measure 6	A constitutional amendment legalizing slot machines	Failed	152,570 (31.98%)	324,548 (68.02%)

Ballot Measures from 1954

Measure name	Description[50]	Status[51]	Yes votes	No votes
Amendment 1	A constitutional amendment granting the public utilities commission regulatory authority	Passed	229,175 (64.90%)	123,932 (35.10%)
Amendment 2	A constitutional amendment excluding the Director of the Water Conservation Board from civil service	Failed	133,073 (45.44%)	159,800 (54.56%)
Amendment 3	A constitutional amendment setting elected state officials terms at four years	Failed	123,112 (44.18%)	155,539 (55.82%)
Amendment 4	A constitutional amendment requiring income deductions from old age pensions	Failed	104,079 (31.73%)	223,965 (68.27%)
Amendment 5	A constitutional amendment reapportioning the General Assembly	Failed	116,695 (42.30%)	159,188 (57.70%)
Referendum 6	An initiative allowing for anticipation warrants for highway purposes	Passed	177,697 (57.26%)	132,628 (42.74%)
Amendment 7	A constitutional amendment modifying personal property taxation	Failed	143,486 (49.14%)	148,517 (50.86%)
Amendment 8	A constitutional amendment setting county officials terms at four years	Passed	168,055 (52.63%)	151,271 (47.37%)

Ballot Measures from 1956

Measure name	Description[52]	Status[53]	Yes votes	No votes
Amendment 1	A constitutional amendment setting elected state officials terms at four years	Passed	316,611 (62.22%)	192,267 (37.78%)
Amendment 2	A constitutional amendment exempting some personal effects from taxation	Passed	320,134 (61.97%)	196,423 (38.03%)
Amendment 3	A constitutional amendment modifying the merit system for civil service	Failed	156,077 (31.82%)	334,498 (68.18%)
Amendment 4	A constitutional amendment reapportioning the General Assembly	Failed	158,204 (31.18%)	349,195 (68.82%)
Amendment 5	A constitutional amendment raising the old age pension to $100 a month and means-testing it (equivalent to $1,121 in 2023)	Passed	364,961 (65.72%)	190,366 (34.28%)

Ballot Measures from 1958

Measure name	Description[54]	Status[55]	Yes votes	No votes
Amendment 1	A constitutional amendment modifying the civil service to make it more competitive	Failed	218,426 (48.52%)	231,725 (51.48%)
Amendment 2	A constitutional amendment modifying the salaries for county and precinct officers	Failed	146,328 (36.65%)	252,903 (63.35%)
Amendment 3	A constitutional amendment modifying county governments	Failed	158,666 (39.64%)	241,636 (60.36%)
Amendment 4	A constitutional amendment legalizing nonprofit lotteries, bingo games, and raffles	Passed	244,929 (50.98%)	235,482 (49.02%)
Amendment 5	A constitutional amendment establishing rules for labor union membership	Failed	200,319 (38.61%)	318,480 (61.39%)

Ballot Measures from 1960

Measure name	Description[56]	Status[57]	Yes votes	No votes
Proposal 1	A constitutional amendment modifying the civil service	Failed	214,956 (38.57%)	342,352 (61.43%)
Proposal 2	A constitutional amendment modifying the election process for county officials	Failed	231,025 (41.31%)	328,241 (58.69%)
Proposal 3	A constitutional amendment creating a department of wildlife conservation	Failed	190,366 (31.24%)	419,048 (68.76%)
Proposal 4	An initiative establishing daylight saving time	Failed	280,115 (45.46%)	336,033 (54.54%)
Proposal 5	A constitutional amendment imposing a sales tax on all items except drugs and food	Failed	200,566 (33.20%)	403,470 (66.80%)
Proposal 7	An initiative exempting some governor appointees from civil service	Failed	170,736 (28.40%)	430,394 (71.60%)

Ballot Measures from 1962

Measure name	Description[58]	Status[59]	Yes votes	No votes
Proposal 1	A constitutional amendment reorganizing the judicial department	Passed	303,740 (64.24%)	169,052 (35.76%)
Proposal 2	A constitutional amendment modifying Denver city and county officers	Failed	157,249 (38.20%)	254,354 (61.80%)
Proposal 3	A constitutional amendment redefining "income" for state purposes	Passed	231,784 (53.46%)	201,795 (46.54%)
Proposal 4	A constitutional amendment establishing minimum voter qualifications	Passed	303,942 (68.88%)	137,323 (31.12%)
Proposal 5	A constitutional amendment modifying property tax assessment procedures	Passed	215,413 (50.34%)	212,477 (49.66%)
Proposal 6	A constitutional amendment changing term lengths for county officials	Failed	207,442 (49.83%)	208,867 (50.17%)
Proposal 7	A constitutional amendment reapportioning the General Assembly	Passed	305,700 (63.90%)	172,725 (36.10%)
Proposal 8	A constitutional amendment creating a reapportionment commission	Failed	149,822 (32.46%)	311,749 (67.54%)

Ballot Measures from 1964

Measure name	Description[60]	Status[61]	Yes votes	No votes
Proposal 1	A constitutional amendment creating a state auditor under the legislature	Passed	304,066 (63.71%)	173,221 (36.29%)
Proposal 2	A constitutional amendment allowing voters to abolish their County Superintendent's office	Passed	308,049 (63.38%)	177,967 (36.62%)

Ballot Measures from 1966

Measure name	Description[62]	Status[63]	Yes votes	No votes
Amendment 1	A constitutional amendment limiting the number of executive departments at the state level to no more than 20	Passed	369,366 (69.51%)	162,038 (30.49%)
Amendment 2	A constitutional amendment creating an ownership tax on motor vehicles	Passed	318,102 (60.10%)	211,177 (39.90%)
Amendment 3	A constitutional amendment creating the Colorado Commission on Judicial Qualifications	Passed	293,771 (52.90%)	261,558 (47.10%)
Amendment 4	A constitutional amendment establishing a 35 member Senate and a 65 member House of Representatives	Passed	374,884 (70.34%)	158,067 (29.66%)
Amendment 5	A constitutional amendment establishing a limit on property tax increases	Failed	178,245 (31.55%)	386,650 (68.45%)
Referred Law 1	An initiative establishing daylight saving time	Passed	346,274 (57.26%)	258,490 (42.74%)
Refereed Law 2	An initiative abolishing the death penalty	Failed	193,245 (33.15%)	389,707 (66.85%)

Ballot Measures from 1968

Measure name	Description[64]	Status[65]	Yes votes	No votes
Amendment 1	A constitutional amendment requiring the Governor and Lieutenant Governor be elected jointly	Passed	428,522 (67.73%)	204,186 (32.27%)
Amendment 2	A constitutional amendment exempting some property from taxation	Failed	284,404 (47.93%)	308,915 (52.07%)
Amendment 3	A constitutional amendment modifying the salaries of county officials	Passed	307,356 (51.50%)	288,873 (48.50%)

Ballot Measures from 1970

Measure name	Description[66]	Status[67]	Yes votes	No votes
Amendment 1	A constitutional amendment exempting department heads from civil service	Passed	293,621 (57.21%)	219,639 (42.89%)
Amendment 2	A constitutional amendment modifying the merit system for state employment	Passed	346,663 (66.40%)	175,076 (33.60%)
Amendment 3	A constitutional amendment allowing counties to have home rule	Passed	325,512 (65.56%)	170,986 (34.44%)
Amendment 4	A constitutional amendment reducing the age and residency requirements for voting	Failed	240,622 (45.19%)	291,858 (54.81%)
Amendment 5	A constitutional amendment modifying residency requirements for voting	Passed	336,977 (64.60%)	184,694 (35.40%)

Ballot Measures from 1972

Measure name	Description[68]	Status[69]	Yes votes	No votes
Measure 1	An initiative to legalize sweepstakes races	Failed	408,704 (49.49%)	417,149 (50.51%)
Measure 2	A constitutional amendment creating a state student loan program	Passed	443,660 (54.13%)	375,948 (45.87%)
Measure 3	A constitutional amendment codifying a right to gender equality	Passed	531,415 (64.28%)	295,254 (35.72%)
Measure 4	A constitutional amendment modifying the structure of the University of Colorado's Board of Regents	Passed	418,825 (52.00%)	386,645 (48.00%)
Measure 5	A constitutional amendment allowing the salaries of elected officials to change while they are in office	Failed	233,678 (29.04%)	571,083 (70.96%)
Measure 6	A constitutional amendment allowing for a private lottery hosted by the United States Sweepstakes Corporation	Failed	161,281 (19.93%)	647,817 (80.06%)
Measure 7	A constitutional amendment limiting property taxes	Failed	192,913 (23.53%)	627,007 (76.47%)
Measure 8	A constitutional amendment preventing the state from instituting new taxes or loaning money for the 1976 Winter Olympics	Passed	514,228 (59.44%)	350,964 (40.56%)
Measure 9	An initiative instituting new transparency requirements for public officials	Passed	491,073 (60.11%)	325,819 (39.89%)
Measure 10	An initiative creating a regulatory agency to govern utility rates	Failed	350,264 (42.80%)	468,154 (57.20%)
Measure 11	An initiative requiring drivers to hold vehicle insurance	Failed	208,155 (25.89%)	595,887 (74.11%)
Measure 12	A constitutional amendment limiting property taxes	Failed	167,882 (21.09%)	628,201 (78.91%)

Ballot Measures from 1974

Measure name	Description[70]	Status[71]	Yes votes	No votes
Amendment 1	A constitutional amendment requiring county territory changes be approved by voters	Passed	409,174 (58.35%)	292,040 (41.65%)
Amendment 2	An initiative imposing the death penalty on people convicted of class 1 felonies	Passed	451,403 (61.15%)	286,805 (38.85%)
Amendment 3	A constitutional amendment requiring regular reports by the State Treasurer	Passed	425,505 (63.26%)	247,141 (36.74%)
Amendment 4	A constitutional amendment allowing localities to invest in energy sector corporations	Passed	481,513 (82.75%)	100,360 (17.25%)
Amendment 5	A constitutional amendment creating a commission to govern Denver's growth	Passed	397,442 (61.17%)	252,256 (38.83%)
Amendment 6	A constitutional amendment modifying the functions of the executive and legislative departments	Passed	386,284 (59.96%)	257,967 (40.04%)
Amendment 7	A constitutional amendment modifying the aviation fuel tax	Passed	375,390 (56.13%)	293,430 (43.87%)
Amendment 8	A constitutional amendment prohibiting forced busing	Passed	485,536 (68.74%)	220,842 (31.26%)
Amendment 9	A constitutional amendment creating the Colorado Reapportionment Commission	Passed	386,725 (60.20%)	255,725 (39.80%)
Amendment 10	A constitutional amendment requiring voter approval before nuclear detonations	Passed	399,818 (57.85%)	291,284 (42.15%)

Ballot Measures from 1976

Measure name	Description[72]	Status[73]	Yes votes	No votes
Measure 1	An initiative authorizing some sweepstakes races	Passed	522,068 (50.53%)	511,135 (49.47%)
Measure 2	A constitutional amendment modifying the way motor vehicles are categorized for tax purposes	Passed	627,562 (61.75%)	388,666 (38.25%)
Measure 3	A constitutional amendment requiring a two-thirds vote in the legislature before the construction of a nuclear power plant	Failed	305,142 (29.34%)	734,843 (70.66%)
Measure 4	A constitutional amendment exempting some state government officials from the standard personnel system	Failed	237,853 (23.63%)	768,687 (76.37%)
Measure 5	A constitutional amendment allowing county commissioners to modify other elected officials' salaries	Failed	376,386 (37.43%)	629,136 (62.57%)
Measure 6	A constitutional amendment revoking the right to gender equality	Failed	401,943 (38.99%)	629,060 (61.01%)
Measure 7	An initiative exempting food from sales tax	Failed	406,311 (38.87%)	639,058 (61.13%)
Measure 8	An initiative requiring the recycling of beverage containers	Failed	346,335 (33.03%)	702,292 (66.97%)
Measure 9	An initiative creating a department to represent public utility customers in government meetings	Failed	304,594 (39.97%)	711,627 (70.03%)
Measure 10	A constitutional amendment requiring voter approval of all taxes	Failed	259,201 (25.25%)	767,157 (74.75%)

Ballot Measures from 1978

Measure name	Description[74]	Status[75]	Yes votes	No votes
Amendment 1	A constitutional amendment clarifying the procedure for replacing county commissioners who resign during their term	Passed	442,071 (66.13%)	226,432 (33.87%)
Amendment 2	A constitutional amendment limiting state spending	Failed	295,616 (41.27%)	420,759 (58.73%)

Ballot Measures from 1980

Measure name	Description[76]	Status[77]	Yes votes	No votes
Amendment 1	A constitutional amendment requiring that measure petition signers also be registered voters	Passed	638,731 (60.14%)	423,322 (39.86%)
Amendment 2	A constitutional amendment creating a state-run lottery	Passed	660,213 (59.83%)	443,289 (40.17%)
Amendment 3	A constitutional amendment allowing towns and cities to annex unincorporated areas with voter approval	Passed	601,302 (56.65%)	460,084 (34.35%)
Amendment 4	A constitutional amendment relating to real estate sales	Failed	381,821 (33.87%)	745,625 (66.13%)
Amendment 5	A constitutional amendment allowing banks to open additional branches	Failed	292,323 (25.58%)	850,454 (74.42%)
Amendment 6	A constitutional amendment restructuring the regional transportation district's board	Passed	570,049 (56.17%)	444,902 (43.83%)

Ballot Measures from 1982

Measure name	Description[78]	Status[79]	Yes votes	No votes
Amendment 1	A constitutional amendment modifying property tax assessments	Passed	551,334 (65.49%)	290,590 (34.51%)
Amendment 2	A constitutional amendment allowing bail to be denied to people accused of capital offenses	Passed	737,813 (82.52%)	156,336 (17.48%)
Amendment 3	A constitutional amendment establishing a system for judicial discipline	Passed	659,905 (77.33%)	193,425 (22.67%)
Amendment 4	A constitutional amendment modifying some legislative procedures	Passed	442,601 (54.27%)	372,897 (45.73%)
Amendment 5	An initiative requiring beverage containers to have a minimum refund value	Failed	242,653 (25.51%)	708,564 (75.45%)
Amendment 6	A constitutional amendment ending nuclear weapons production	Failed	325,985 (36.60%)	564,606 (63.40%)
Amendment 7	An initiative allowing grocery stores to sell wines with alcohol contents below 14%	Failed	333,467 (35.00%)	620,190 (65.00%)

Ballot Measures from 1984

Measure name	Description[80]	Status[81]	Yes votes	No votes
Amendment 1	A constitutional amendment creating the office of the Commissioner of Insurance	Passed	641,587 (58.81%)	449,362 (41.19%)
Amendment 2	A constitutional amendment requiring voter registration for all election types	Passed	811,130 (72.73%)	304,208 (27.27%)
Amendment 3	A constitutional amendment prohibiting the use of state funds for abortion	Passed	627,343 (50.39%)	617,637 (49.61%)
Amendment 4	An initiative allowing voter registration alongside driver's license applications	Passed	705,725 (61.18%)	447,803 (38.82%)
Amendment 5	A constitutional amendment allowing some forms of casino gambling	Failed	406,989 (33.18%)	819,533 (66.82%)

Ballot Measures from 1986

Measure name	Description[82]	Status[83]	Yes votes	No votes
Amendment 1	A constitutional amendment modifying the merit system for state employment	Failed	461,004 (48.57%)	488,226 (51.43%)
Amendment 2	A constitutional amendment allowing county commissioners to modify other elected officials salaries	Failed	406,960 (45.24%)	492,511 (54.76%)
Amendment 3	A constitutional amendment requiring that home rule municipalities abide by an initiative and referendum system	Passed	455,053 (53.42%)	396,738 (46.58%)
Amendment 4	A constitutional amendment preventing new taxes without voter approval	Failed	375,097 (37.50%)	625,158 (62.50%)

Ballot Measures from 1988

Measure name	Description[84]	Status[85]	Yes votes	No votes
Amendment 1	A constitutional amendment making English the official state language	Passed	829,617 (61.15%)	527,053 (38.85%)
Amendment 2	A constitutional amendment modifying expenses reimbursements	Passed	645,002 (53.93%)	551,118 (46.07%)
Amendment 3	A constitutional amendment restricting General Assembly sessions to no more than 120 days	Passed	641,363 (52.33%)	584,359 (47.77%)
Amendment 4	A constitutional amendment creating an eight-hour workday, modifying age qualifications to vote, and repealing some obsolete provisions	Passed	799,250 (67.21%)	389,906 (32.79%)
Amendment 5	A constitutional amendment exempting some forms of property from taxation	Passed	624,021 (51.90%)	578,295 (48.10%)
Amendment 6	A constitutional amendment requiring voter approval for new taxes	Failed	567,884 (42.19%)	778,075 (57.81%)
Amendment 7	A constitutional amendment allowing state funds to be used for abortion	Failed	534,070 (39.76%)	809,078 (60.24%)
Amendment 8	A constitutional amendment modifying some General Assembly procedures	Passed	852,448 (71.96%)	332,159 (28.04%)

Ballot Measures from 1990

Measure name	Description[86]	Status[87]	Yes votes	No votes
Amendment 1	A constitutional amendment requiring voter approval for some tax increases	Failed	494,934 (48.93%)	516,534 (51.07%)
Amendment 2	A referendum modifying the presidential primary system	Passed	582,835 (61.16%)	370,166 (38.84%)
Amendment 3	A constitutional amendment repealing some obsolete provisions	Passed	717,544 (77.84%)	204,294 (22.16%)
Amendment 4	A constitutional amendment allowing limited gambling in Black Hawk, Central, and Cripple Creek cities	Passed	574,620 (57.31%)	428,096 (42.39%)
Amendment 5	A constitutional amendment instituting term limits for most statewide elected officials	Passed	708,975 (70.99%)	289,664 (29.01%)

Ballot Measures from 1992

Measure name	Description[88]	Status[89]	Yes votes	No votes
Amendment 1	A constitutional amendment establishing a Taxpayer Bill of Rights (TABOR)	Passed	812,308 (53.68%)	700,906 (46.32%)
Amendment 2	A constitutional amendment prohibiting local governments for granted protected status to sexual orientation	Passed	813,966 (53.41%)	710,151 (46.59%)
Amendment 3	A constitutional amendment authorizing some forms of gambling in a variety of cities and counties	Failed	448,779 (29.74%)	1,060,168 (70.26%)
Amendment 4	A constitutional amendment authorizing some forms of gambling in a variety of cities and counties	Failed	414,699 (27.61%)	1,087,136 (72.39%)
Amendment 5	A constitutional amendment authorizing some forms of gambling in Parachute	Failed	414,489 (27.59%)	1,087,713 (72.41%)
Amendment 6	An initiative requiring state-wide educational standards, testing, and implementing a wide variety of school funding reforms	Failed	693,231 (45.61%)	826,787 (54.39%)
Amendment 7	A constitutional amendment creating a voucher program for schools	Failed	503,162 (33.21%)	1,011,901 (55.79%)
Amendment 8	A constitutional amendment creating the Great Outdoors Colorado Program	Passed	876,424 (58.20%)	629,490 (41.80%)
Amendment 9	A constitutional amendment allowing limited gambling in the Central Platte Valley	Failed	292,961 (19.62%)	1,200,336 (80.38%)
Amendment 10	An initiative banning the use of bait and dogs in black bear hunting	Passed	1,054,032 (69.70%)	458,260 (30.30%)
Referendum A	A constitutional amendment establishing victim rights	Passed	1,139,427 (80.18%)	281,731 (19.82%)
Referendum B	A constitutional amendment repealing some obsolete provisions	Passed	1,081,463 (78.02%)	304,718 (21.98%)
Referendum C	A constitutional amendment allowing for limited gambling in localities with voter approval	Passed	1,075,649 (76.01%)	339,521 (23.99%)

Ballot Measures from 1993

Measure name	Description[90]	Status[91]	Yes votes	No votes
Referendum A	An initiative establishing a sales tax on tourist-related items for the purpose of funding tourism marketing	Failed	274,989 (44.82%)	338,546 (55.18%)

Ballot Measures from 1994

Measure name	Description[92]	Status[91]	Yes votes	No votes
Amendment 1	A constitutional amendment increasing the cigarette tax rate to 50%	Failed	429,847 (38.53%)	685,860 (61.47%)
Amendment 11	A constitutional amendment increasing the benefits of worker's compensation insurance	Failed	369,741 (33.59%)	730,963 (66.41%)
Amendment 12	A constitutional amendment substantially modifying campaign contribution rules	Failed	246,723 (22.53%)	848,140 (77.47%)
Amendment 13	A constitutional amendment allowing airports to host slot machines and allowing limited gambling in Manitou Springs	Failed	90,936 (8.28%)	1,007,557 (91.72%)
Amendment 15	A constitutional amendment requiring that at least 60% of candidate contributions come from individuals rather than organizations	Failed	508,029 (46.35%)	588,072 (53.65%)
Amendment 16	A constitutional amendment preventing the state judiciary from restricting freedom of speech past existing federal precedent	Failed	404,156 (36.73%)	696,040 (63.27%)
Amendment 17	A constitutional amendment placing term limits on a variety of public offices	Passed	554,238 (51.05%)	531,521 (48.95%)
Amendment 18	A constitutional amendment relating to financial responsibility for medical assistance	Failed	334,029 (31.85%)	714,653 (68.15%)
Referendum A	A constitutional amendment requiring that ballot measures placed via petition be confined to a single subject	Passed	687,527 (65.68%)	359,298 (34.32%)
Referendum B	A constitutional amendment requiring the publication of a nonpartisan voter information pamphlet every election	Passed	529,749 (50.44%)	520,438 (49.56%)
Referendum C	A constitutional amendment denying bail to people accused of violent felonies	Passed	822,632 (76.93%)	246,726 (23.07%)

Ballot Measures from 1995

Measure name	Description[93]	Status[94]	Yes votes	No votes
Referendum A	A referendum allowing the state to incur debt for the purposes of funding prisons	Failed	291,736 (45.11%)	355,031 (54.89%)

Ballot Measures from 1996

Measure name	Description[95]	Status[94]	Yes votes	No votes
Amendment 11	A constitutional amendment eliminating many property tax exemptions	Failed	242,543 (16.68%)	1,211,637 (83.32%)
Amendment 12	A constitutional amendment setting term limits for many public offices and proposing a federal amendment to the same effect	Passed	768,257 (54.01%)	654,124 (45.99%)
Amendment 13	A constitutional amendment modifying the ballot measure process	Failed	435,995 (31.07%)	967,266 (68.93%)
Amendment 14	A constitutional amendment prohibiting leghold traps, body-gripping traps, poisons, and snares for hunting	Passed	752,413 (52.10%)	691,733 (47.90%)
Amendment 15	An initiative limiting political campaign contributions	Passed	928,148 (65.79%)	482,551 (34.21%)
Amendment 16	A constitutional amendment modifying some rules relating to state lands held in trust	Passed	708,502 (51.92%)	656,095 (48.08%)
Amendment 17	A constitutional amendment specifying that parents have the right to control their children's upbringing, education, values, and discipline	Failed	615,202 (42.35%)	837,606 (57.65%)
Amendment 18	A constitutional amendment allowing some forms of gambling in Trinidad	Failed	440,173 (31.46%)	958,991 (68.54%)
Referendum A	A constitutional amendment requiring that proposed constitutional amendments reach a 60% vote threshold to pass	Failed	544,543 (40.89%)	787,134 (59.11%)
Referendum B	A constitutional amendment lengthening the time between the mailing of voter information pamphlets and ballots	Passed	739,435 (54.87%)	608,219 (45.13%)
Referendum C	A constitutional amendment authorizing the General Assembly to regulate county sheriff's offices	Passed	754,339 (56.10%)	590,402 (43.90%)
Referendum D	A constitutional amendment modifying unemployment compensation insurance	Failed	376,860 (29.32%)	908,476 (70.68%)

Ballot Measures from 1997

Measure name	Description[96]	Status[97]	Yes votes	No votes
Amendment 1	A constitutional amendment raising the fuel tax and vehicle registration fees for the purpose of funding the Transportation Department	Failed	109,663 (15.79%)	585,055 (84.21%)

Ballot Measures from 1998

Measure name	Description[98]	Status[97]	Yes votes	No votes
Amendment 11	A constitutional amendment prohibiting partial-birth abortions	Failed	617,977 (48.52%)	617,977 (51.48%)
Amendment 12	An initiative requiring parental notification before an abortion is performed on an emancipated minor	Passed	707,021 (54.87%)	581,481 (45.13%)
Amendment 13	A constitutional amendment requiring uniform application of livestock laws	Failed	475,664 (38.70%)	753,509 (61.30%)
Amendment 14	An initiative increasing regulations of commercial hog farms	Passed	790,825 (64.21%)	440,766 (35.79%)
Amendment 15	An initiative requiring that water flow meters in the San Luis Valley be certified by the state engineer	Failed	292,977 (23.83%)	936,698 (76.17%)
Amendment 16	A constitutional amendment instituting fees on water pumped from state lands in the Rio Grande Water Conservation District	Failed	297,872 (24.23%)	931,566 (75.77%)
Amendment 17	A constitutional amendment granting a tax credit to the parents of schoolchildren	Failed	515,942 (39.72%)	782,982 (60.28%)
Amendment 18	A constitutional amendment allowing candidates for public office to submit declarations of voluntary term limits	Passed	613,557 (50.41%)	603,651 (49.59%)
Referendum A	A constitutional amendment relating to healthcare	Failed	505,903 (45.32%)	610,449 (54.68%)
Referendum B	An initiative allowing the state to hold up to $200,000,000 in excess tax revenue for the purpose of funding school construction and transportation (equivalent to $373,866,884 in 2023)	Failed	477,504 (38.41%)	765,654 (61.59%)
Referendum C	A constitutional amendment creating the city and county of Broomfield	Passed	670,781 (61.29%)	423,603 (38.71%)

Ballot Measures from 1999

Measure name	Description[99]	Status[97]	Yes votes	No votes
Referendum A	A referendum allowing the state to take on additional debt for the purpose of funding transportation projects	Passed	477,982 (61.68%)	296,971 (38.32%)

Ballot Measures from 2000

Measure name	Description[100]	Status[101]	Yes votes	No votes
Amendment 20	A constitutional amendment legalizing medical marijuana	Passed	915,527 (53.53%)	786,983 (46.47%)
Amendment 21	A constitutional amendment introducing small tax cuts	Failed	569,788 (33.98%)	1,107,155 (66.02%)
Amendment 22	An initiative requiring background checks on gun purchases at gun shows	Passed	1,197,593 (70.05%)	512,084 (29.95%)
Amendment 23	A constitutional amendment modifying public school funding	Passed	882,628 (52.71%)	791,934 (47.29%)
Amendment 24	A constitutional amendment requiring voter approval for local government development plans	Failed	511,885 (30.11%)	1,888,138 (69.89%)
Amendment 25	A constitutional amendment requiring a 24-hour waiting period before abortions	Failed	664,420 (39.44%)	1,020,029 (60.56%)
Referendum A	A constitutional amendment establishing a homestead tax exemption for senior citizens	Passed	843,620 (54.74%)	697,398 (45.26%)
Referendum B	A constitutional amendment modifying the timeframe for adoption of a redistricting plan for the General Assembly	Passed	852,098 (60.48%)	556,769 (39.52%)
Referendum C	A constitutional amendment modifying the selection process for county surveyors	Failed	661,704 (45.45%)	794,310 (54.55%)
Referendum D	A constitutional amendment removing some outdated provisions	Passed	1,063,345 (71.56%)	422,629 (28.44%)
Referendum E	An initiative allowing Colorado to enter multi-state lotteries	Passed	836,390 (51.64%)	783,275 (48.36%)
Referendum F	An initiative allowing the state to utilize excess state revenues for the purpose of funding school performance grants	Failed	697,673 (44.11%)	887,947 (55.89%)

Ballot Measures from 2001

Measure name	Description[102]	Status[103]	Yes votes	No votes
Amendment 26	An initiative allowing the state to spend $50,000,000 for the purpose of improving Interstate 70 (equivalent to $86,036,459 in 2023)	Failed	283,184 (34.10%)	547,213 (65.90%)
Referendum A	An initiative increasing the outdoor recreation trust fund by $115,000,000 (equivalent to $197,883,856 in 2023)	Passed	478,501 (57.58%)	352,585 (42.42%)

Ballot Measures from 2002

Measure name	Description[25]	Status[103]	Yes votes	No votes
Amendment 27	A constitutional amendment limiting corporation and labor union contributions to political campaigns	Passed	890,390 (66.50%)	448,599 (33.50%)
Amendment 28	An initiative requiring voting by mail	Failed	557,573 (42.41%)	757,299 (57.59%)
Amendment 29	An initiative substantially modifying the candidate selection process for primary elections	Failed	509,109 (39.84%)	768,683 (60.14%)
Amendment 30	A constitutional amendment allowing same-day voter registration	Failed	530,442 (39.25%)	821,050 (60.75%)
Amendment 31	A constitutional amendment prohibiting bilingual education in most circumstances	Failed	608,264 (43.78%)	781,016 (56.22%)
Referendum A	A constitutional amendment eliminating term limits for district attorneys	Failed	461,848 (35.27%)	847,602 (64.73%)
Referendum B	A constitutional amendment allowing localities to co-own healthcare facilities with private companies	Failed	510,209 (40.76%)	741,568 (59.24%)
Referendum C	A constitutional amendment allowing the General Assembly to regulate the position of county coroner	Passed	900,611 (70.92%)	369,351 (29.08%)
Referendum D	A constitutional amendment removing some obsolete provisions	Passed	899,914 (71.89%)	351,886 (28.11%)
Referendum E	A referendum establishing March 31 as "Cesar Chavez Day"	Failed	275,947 (20.61%)	1,062,780 (79.39%)

Ballot Measures from 2003

Measure name	Description[104]	Status[105]	Yes votes	No votes
Amendment 32	A constitutional amendment modifying property tax assessment	Failed	203,449 (22.45%)	702,829 (77.55%)
Amendment 33	A constitutional amendment allowing some limited forms of gambling	Failed	180,959 (19.09%)	766,893 (80.91%)
Referendum A	An referendum allowing the state to borrow up to $2,000,000,000 to fund water projects (equivalent to $3,312,590,449 in 2023)	Failed	307,412 (32.87%)	627,716 (67.13%)

Ballot Measures from 2004

Measure name	Description[106]	Status[105]	Yes votes	No votes
Amendment 34	A constitutional amendment prohibiting laws which would limit property owner's ability to recover damages from construction projects	Failed	469,566 (23.45%)	1,533,002 (76.55%)
Amendment 35	A constitutional amendment raising the tobacco tax for the purpose of funding educational and preventive health programs	Passed	1,258,086 (61.38%)	791,627 (38.62%)
Amendment 36	A constitutional amendment allowing Colorado's electoral votes to be distributed proportionally	Failed	696,770 (34.78%)	1,306,834 (65.22%)
Amendment 37	An initiative requiring that a certain percentage of electricity be generated from renewable sources	Passed	1,066,023 (53.61%)	922,577 (46.39%)
Referendum A	A constitutional amendment substantially modifying the state civil service system	Failed	696,007 (39.19%)	1,080,136 (60.81%)
Referendum B	A constitutional amendment removing some obsolete provisions relating to education	Passed	1,247,998 (69.00%)	560,811 (31.00%)

Ballot Measures from 2005

Measure name	Description[107]	Status[108]	Yes votes	No votes
Referendum C	An initiative allowing the state to spend money collected over the TABOR limit on health care, public education, transportation, and fire and police projects	Passed	600,222 (52.06%)	552,662 (47.94%)
Referendum D	An initiative allowing the state to borrow up to $2,000,720,000 (equivalent to $3,121,245,923 in 2023)	Failed	567,540 (49.38%)	581,751 (50.62%)

Ballot Measures from 2006

Measure name	Description[109]	Status[108]	Yes votes	No votes
Amendment 38	A constitutional amendment expanding the ability for citizens to place measures on the ballot	Failed	456,468 (30.67%)	1,027,550 (69.24%)
Amendment 39	A constitutional amendment requiring that 65% of school district budgets be allocated towards classroom instruction	Failed	569,483 (37.61%)	944,735 (62.39%)
Amendment 40	A constitutional amendment introducing term limits for judges in the Colorado Supreme Court and Colorado Court of Appeals	Failed	648,199 (42.91%)	862,349 (57.09%)
Amendment 41	A constitutional amendment prohibiting elected officials and their family members from accepting gifts and restricting former elected official's abilities to become lobbyists	Passed	938,888 (62.57%)	561,646 (37.43%)
Amendment 42	A constitutional amendment increasing the minimum wage and tying it to inflation	Passed	823,526 (53.30%)	721,530 (46.70%)
Amendment 43	A constitutional amendment prohibiting same-sex marriages	Passed	855,126 (55.02%)	699,030 (44.98%)
Amendment 44	An initiative legalizing the possession of marijuana in small amounts	Failed	636,938 (41.08%)	913,411 (58.92%)
Referendum E	A constitutional amendment providing a property tax exemption to some disabled veterans	Passed	1,195,907 (79.24%)	313,292 (20.76%)
Referendum F	A constitutional amendment removing some deadlines relating to recall elections	Failed	626,015 (44.68%)	775,207 (55.32%)
Referendum G	A constitutional amendment eliminating some obsolete provisions	Passed	1,092,293 (76.08%)	343,495 (23.92%)
Referendum H	An initiative relating to the income tax deduction limit	Passed	744,475 (50.74%)	722,651 (49.26%)
Referendum I	An initiative granting same-sex couples the same rights as other domestic partnerships	Failed	734,385 (47.65%)	806,717 (52.35%)
Referendum J	An initiative requiring that school districts spend at least 65% of their budget on student achievement-related services	Failed	620,790 (41.53%)	874,151 (58.47%)
Referendum K	An initiative requiring the Attorney General of Colorado to engage in a lawsuit against the United States to force the enforcement of existing immigration laws	Passed	830,628 (55.72%)	660,012 (44.28%)

Ballot Measures from 2008

Measure name	Description[110]	Status[111]	Yes votes	No votes
Amendment 46	A constitutional amendment prohibiting discrimination and preferential treatment in public employment, education, and contracting	Failed	1,102,046 (49.19%)	1,138,134 (50.81%)
Amendment 47	A constitutional amendment prohibition union contracts which require employees to pay fees to stay employed	Failed	1,003,056 (43.89%)	1,282,501 (56.11%)
Amendment 48	A constitutional amendment defining personhood as beginning at conception	Failed	618,779 (26.79%)	1,691,237 (73.21%)
Amendment 49	A constitutional amendment prohibiting public employers from using payroll deductions to benefit private organizations	Failed	882,428 (39.24%)	1,366,620 (60.76%)
Amendment 50	A constitutional amendment allowing some forms of gambling in Central, Black Hawk, and Cripple Creek cities	Passed	1,330,566 (58.70%)	936,254 (41.30%)
Amendment 51	A constitutional amendment increasing the sales tax for the purpose of funding services for the developmentally disabled	Failed	853,211 (37.63%)	1,414,065 (62.37%)
Amendment 52	A constitutional amendment creating a trust fund for highway development	Failed	790,124 (35.78%)	1,418,009 (64.22%)
Amendment 54	A constitutional amendment limiting campaign contributions from government contract holders	Passed	1,130,098 (51.21%)	1,076,694 (48.79%)
Amendment 58	An initiative modifying the severance tax	Failed	944,191 (41.95%)	1,306,782 (58.05%)
Amendment 59	A constitutional amendment relating to education funding and rebates	Failed	1,010,409 (45.69%)	1,201,220 (54.31%)
Referendum L	A constitutional amendment lowering the age requirement to serve as a General Assembly member to 21	Failed	1,010,896 (46.50%)	1,162,296 (53.50%)
Referendum M	A constitutional amendment eliminating some obsolete provisions relating to land value increases	Passed	1,307,770 (62.26%)	792,678 (37.74%)
Referendum N	A constitutional amendment eliminating some obsolete provisions relating to alcohol	Passed	1,449,383 (68.75%)	658,684 (31.25%)
Referendum O	A constitutional amendment modifying the requirements to place ballot measures on the ballot	Failed	1,004,925 (47.50%)	1,110,877 (52.50%)

Ballot Measures from 2010

Measure name	Description[112]	Status[113]	Yes votes	No votes
Amendment P	A constitutional amendment transferring regulatory power over gambling from the Department of State to the Department of Revenue	Failed	611,664 (37.67%)	1,012,193 (62.33%)
Amendment Q	A constitutional amendment establishing some government continuity procedures	Passed	944,446 (57.52%)	697,373 (42.48%)
Amendment R	A constitutional amendment eliminating property taxes for some owners	Failed	616,516 (38.34%)	991,347 (61.66%)
Amendment 60	A constitutional amendment limiting property tax increases	Failed	427,912 (24.50%)	1,318,507 (75.50%)
Amendment 61	A constitutional amendment prohibiting state and local governments from borrowing money without voter approval	Failed	474,772 (26.99%)	1,284,307 (73.01%)
Amendment 62	A constitutional amendment defining personhood as beginning at conception	Failed	509,062 (29.47%)	1,218,490 (70.53%)
Amendment 63	A constitutional amendment preventing the establishment of a universal healthcare system	Failed	800,155 (46.90%)	905,944 (53.10%)
Proposition 101	An initiative substantially reforming the motor vehicle, income, and telecom taxes	Failed	564,588 (32.31%)	1,183,000 (67.69%)
Proposition 102	An initiative allowing first-time offenders of nonviolent misdemeanors to be released pretrial without bail	Failed	636,444 (38.03%)	1,037,103 (61.97%)

Ballot Measures from 2011

Measure name	Description[114]	Status[115]	Yes votes	No votes
Proposition 103	An initiative increasing the state income and sales tax	Failed	349,746 (36.30%)	611,907 (63.60%)

Ballot Measures from 2012

Measure name	Description[116]	Status[115]	Yes votes	No votes
Amendment 64	A constitutional amendment legalizing marijuana	Passed	1,383,139 (55.32%)	1,116,894 (44.68%)
Amendment 65	A constitutional amendment relating to corporate contributions to political campaigns	Passed	1,762,515 (74.01%)	619,073 (25.99%)
Amendment S	A constitutional amendment modifying the state personnel system	Passed	1,276,405 (56.35%)	988,541 (43.65%)

Ballot Measures from 2013

Measure name	Description[117]	Status[118]	Yes votes	No votes
Proposition AA	An initiative imposing several new taxes on marijuana sales for the purpose of funding school construction and marijuana regulation	Passed	902,181 (65.27%)	479,992 (34.73%)
Amendment 66	A constitutional amendment raising some state taxes for the purpose of funding education	Failed	496,151 (35.54%)	899,927 (64.46%)

Ballot Measures from 2014

Measure name	Description[119]	Status[118]	Yes votes	No votes
Amendment 67	A constitutional amendment redefining the terms "person" and "child" to include human fetuses	Failed	702,544 (35.13%)	1,297,299 (64.87%)
Amendment 68	A constitutional amendment allowing limited gambling at some horse racetracks for the purpose of funding a kindergarten fund	Failed	597,239 (29.62%)	1,419,095 (70.38%)
Proposition 104	An initiative requiring collective bargaining negotiations for school employees to be open to the public	Passed	1,364,747 (70.09%)	582,473 (29.91%)
Proposition 105	An initiative requiring that food containing GMOs carry a label clearly identifying them as such	Failed	694,738 (34.53%)	1,317,288 (65.47%)

Ballot Measures from 2015

Measure name	Description[120]	Status[121]	Yes votes	No votes
Proposition BB	An initiative allowing the state to retain $66,000,000 in marijuana tax revenues for the purpose of funding school construction projects	Passed	847,380 (69.39%)	373,734 (30.61%)

Ballot Measures from 2016

Measure name	Description[122]	Status[121]	Yes votes	No votes
Amendment T	A constitutional amendment prohibiting slavery as a punishment for a crime	Failed	1,280,037 (49.68%)	1,296,722 (50.32%)
Amendment U	A constitutional amendment exempting some assets from taxation	Failed	1,103,593 (43.85%)	1,412,923 (56.15%)
Amendment 69	A constitutional amendment creating a universal healthcare system for Colorado residents	Failed	568,683 (21.23%)	2,109,868 (78.77%)
Amendment 70	A constitutional amendment raising the minimum wage to $12.00 an hour	Passed	1,517,903 (55.36%)	1,224,189 (44.64%)
Amendment 71	A constitutional amendment requiring initiative petitioners to gather signatures in all 35 state senate districts and imposing a 55% vote threshold for future constitutional amendments	Passed	1,476,948 (55.69%)	1,175,324 (44.31%)
Amendment 72	An initiative raising taxes on cigarettes by $1.75	Failed	1,286,851 (46.94%)	1,454,342 (53.06%)
Proposition 106	An initiative legalizing assisted death	Passed	1,765,786 (64.87%)	956,263 (35.13%)
Proposition 107	An initiative creating an open primary system for presidential elections	Passed	1,701,599 (64.09%)	953,246 (35.91%)
Proposition 108	An initiative allowing unaffiliated electors to vote in primary elections	Passed	1,398,577 (53.27%)	1,227,117 (46.73%)

Ballot Measures from 2018

Measure name	Description[123]	Status[124]	Yes votes	No votes
Amendment A	A constitutional amendment prohibiting slavery as a punishment for a crime	Passed	1,599,790 (66.21%)	816,342 (33.79%)
Amendment V	A constitutional amendment lowering the minimum age for state legislators from 25 to 21	Failed	889,179 (36.19%)	1,567,560 (63.81%)
Amendment W	A constitutional amendment allowing county clerks to consolidate judge retention questions on election ballots	Failed[d]	1,262,713 (53.81%)	1,083,712 (46.19%)
Amendment X	A constitutional amendment redefining "industrial hemp"	Passed	1,421,630 (60.64%)	922,597 (39.36%)
Amendment Y	A constitutional amendment creating a 12-member redistricting committee for congressional districts	Passed	1,711,008 (71.37%)	686,260 (28.63%)
Amendment Z	A constitutional amendment creating a 12-member redistricting committee for General Assembly districts	Passed	1,687,583 (71.07%)	687,113 (28.93%)
Amendment 73	A constitutional amendment establishing a graduated income tax	Failed	1,137,527 (46.43%)	1,312,331 (53.57%)
Amendment 74	A constitutional amendment requiring property owners be compensated if their property value decreased due to changes in state law	Failed	1,139,205 (46.42%)	1,315,182 (53.58%)
Amendment 75	A constitutional amendment allowing candidates in races where a self-funded candidate gives their campaign at least $1,000,000 to accept more than the standard campaign contribution limit	Failed	813,861 (34.04%)	1,576,835 (65.96%)
Proposition 109	An initiative allowing the state to issue $3,500,000,000 in bonds for the purpose of funding statewide transportation projects	Failed	952,814 (39.28%)	1,472,933 (60.72%)
Proposition 110	An initiative authorizing the state to issue $6,000,000,000 in bonds for the purpose of funding statewide transportation projects and raising the state sales tax rate	Failed	990,287 (40.61%)	1,448,535 (59.39%)
Proposition 111	An initiative capping payday loan interest rates	Passed	1,865,200 (77.25%)	549,357 (22.75%)
Proposition 112	An initiative mandating that new fracking projects be at least 2,500 feet from occupied buildings	Failed	1,116,738 (44.88%)	1,371,284 (55.12%)

Ballot Measures from 2019

Measure name	Description[125]	Status[126]	Yes votes	No votes
Proposition CC	An initiative allowing the state to retain excess revenue and direct it towards transportation and education programs	Failed	724,060 (46.34%)	838,282 (53.66%)
Proposition DD	An initiative legalizing sports betting	Passed	800,745 (51.41%)	756,712 (48.59%)

Ballot Measures from 2020

Measure name	Description[127]	Status[128]	Yes votes	No votes
Amendment B	A constitutional amendment repealing the Gallagher Amendment	Passed	1,740,395 (57.52%)	1,285,136 (42.48%)
Amendment C	A constitutional amendment lowering the entry requirements for charitable lotteries	Failed[d]	1,586,973 (52.35%)	1,444,553 (47.65%)
Amendment 76	A constitutional amendment restricting voting to United States citizens	Passed	1,985,239 (62.90%)	1,171,137 (37.10%)
Amendment 77	A constitutional amendment allowing voters in Central, Black Hawk, and Cripple Creek cities to expand gambling	Passed	1,854,153 (60.54%)	1,208,414 (39.46%)
Proposition EE	An initiative to tax nicotine products for the purpose of funding health and education programs	Passed	2,134,608 (67.56%)	1,025,182 (32.44%)
Proposition 113	A referendum to uphold Colorado's membership in the National Popular Vote Interstate Compact	Passed	1,644,716 (52.33%)	1,498,500 (47.67%)
Proposition 114	An initiative requiring the Colorado Parks and Wildlife Commission to create a management plan to reintroduce gray wolves	Passed	1,590,299 (50.91%)	1,533,313 (49.09%)
Proposition 115	An initiative banning abortions after 22 weeks	Failed	1,292,787 (41.01%)	1,859,479 (58.99%)
Proposition 116	An initiative decreasing state income tax rates from 4.63% to 4.55%	Passed	1,821,702 (57.86%)	1,327,025 (42.14%)
Proposition 117	An initiative requiring statewide voter approval for some new state enterprises	Passed	1,573,114 (52.55%)	1,420,445 (47.45%)
Proposition 118	An initiative creating a paid family and medical leave program	Passed	1,804,546 (57.75%)	1,320,386 (42.25%)

Ballot Measures from 2021

Measure name	Description[129]	Status[130]	Yes votes	No votes
Amendment 78	A constitutional amendment transferring power over custodial funds from the state treasurer to the General Assembly	Failed	646,983 (43.03%)	856,704 (56.97%)
Proposition 119	An initiative raising the marijuana sales tax for the purpose of funding a Learning Enrichment and Academic Progress Program	Failed	701,479 (45.75%)	831,670 (54.25%)
Proposition 120	An initiative modifying property tax rates and allowing the state to spend $25,000,000 over the TABOR cap to reimburse localities for lost revenue	Failed	652,382 (42.96%)	866,197 (57.04%)

Ballot Measures from 2022

Measure name	Description[131]	Status[132]	Yes votes	No votes
Amendment D	A constitutional amendment directing the Governor to assign judges to Colorado's 23rd judicial district	Passed	1,502,866 (67.38%)	727,409 (32.62%)
Amendment E	A constitutional amendment extending a property tax exemption to the surviving spouses of deceased military service members	Passed	2,109,471 (87.93%)	298,514 (12.07%)
Amendment F	A constitutional amendment modifying the rules relating to charitable gaming	Failed	930,370 (40.64%)	1,359,027 (59.36%)
Proposition FF	An initiative reducing the income tax deduction for some income brackets for the purpose of funding school meals	Passed	1,384,852 (56.75%)	1,055,583 (43.25%)
Proposition GG	An initiative requiring that ballot measures changing income taxes break down their impact by tax bracket	Passed	1,704,757 (71.92%)	665,476 (28.08%)
Proposition 121	An initiative decreasing the state income tax rate from 4.55% to 4.40%	Passed	1,581,163 (65.24%)	842,506 (34.76%)
Proposition 122	An initiative decriminalizing some psychedelic plants and fungi[133]	Passed	1,269,992 (53.64%)	1,121,124 (46.36%)
Proposition 123	An initiative creating a state affordable housing fund	Passed	1,269,816 (52.61%)	1,143,974 (47.39%)
Proposition 124	An initiative increasing the number of liquor store licenses any single individual can hold	Failed	905,565 (37.69%)	1,497,346 (62.31%)
Proposition 125	An initiative allowing stores that are licensed to sell beer for off-site consumption to also sell wine for off-site consumption	Passed	1,228,404 (50.58%)	1,200,219 (49.42%)
Proposition 126	An initiative allowing stores that are licensed to sell alcohol for off-site consumption to also offer delivery	Failed	1,183,059 (48.86%)	1,238,074 (51.14%)

Measure name	Description[134]	Status[135]	Yes votes	No votes
Proposition HH	A measure modifying the level and distribution of property taxes	Failed	682,667 (40.69%)	995,259 (59.31%)
Proposition II	A measure requiring the state to spend excess tobacco tax revenues from 2020's Proposition EE on preschool education programs	Passed	1,130,047 (67.53%)	543,405 (32.47%)

Measure name	Description[136]	Status	Yes votes	No votes
Amendment G	A constitutional amendment expanding veterans who qualify for property tax exemptions.	Election not yet held
Amendment H	A constitutional amendment modifying judicial discipline procedures.	Election not yet held
Amendment I	A constitutional amendment granting exceptions to the right to bail for certain violent crimes.	Election not yet held
Amendment J	A constitutional amendment repealing the definition of marriage as between a man and a woman.	Election not yet held
Amendment K	A constitutional amendment modifying deadlines for petitioning ballot initiatives.	Election not yet held
Amendment 79	A constitutional amendment to guarantee the right to an abortion.	Election not yet held
Amendment 80	A constitutional amendment to guarantee the right to school choice.	Election not yet held
Proposition JJ	A measure to retain taxes already collected by the state from sports betting.	Election not yet held
Proposition KK	A measure to raise taxes on firearms and ammunition to fund gun safety measures.	Election not yet held
Proposition 127	A measure prohibiting the hunting of mountain lions, lynxes, and bobcats.	Election not yet held
Proposition 128	A measure to require certain convicted criminals to serve no less than 85% of their sentence.	Election not yet held
Proposition 129	A measure to create a veterinary professional associates position in Colorado.	Election not yet held
Proposition 130	A measure to increase state funding for law enforcement agencies.	Election not yet held
Proposition 131	A measure to implement blanket primary elections and ranked-choice general elections.	Election not yet held

• Initiatives and referendums in the United States
• History of Colorado
• Law of Colorado