The district had 168,561 registered voters as of December 1, 2021[update], of whom 68,776 (40.8%) were registered as unaffiliated, 63,444 (37.6%) were registered as Republicans, 34,659 (20.6%) were registered as Democrats, and 1,682 (1.0%) were registered to other parties.[5]
When the 40-district legislative map was created in 1973, the 30th district was based in Essex and Hudson counties. It consisted of the Ironbound neighborhood and a part of the North Ward of Newark and Belleville in Essex County, and Harrison, East Newark, Kearny, and Secaucus in Hudson County.[7] This district elected one of the few independents ever elected to the Legislature when in 1973, controversial Newark activist Anthony Imperiale won a term in the Senate in 1973, though he would later serve in the Assembly from the district as a Republican.[8] In the 1980s, the 30th shifted slightly to the northwest when it encompassed Belleville, Bloomfield, Nutley, Glen Ridge, Montclair, Verona, and Cedar Grove, entirely in Essex County.[9]
As the population began to shift away from the immediate suburbs of New Jersey cities in the 1980s, the 1991 Apportionment Commission using data collected from the 1990 census eliminated the 30th district as it existed in Essex County and shifted it to the fast-growing areas of Burlington, Monmouth, and Ocean counties.[10][11] The new 30th district created in 1991 consisted of northern corner of Burlington County including Pemberton Borough and Township, Eastampton Township, Florence Township, Bordentown City and Township, the four panhandle municipalities of Monmouth County (Allentown, Upper Freehold Township, Roosevelt, and Millstone Township), and Ocean County's Plumsted, Jackson, and Lakewood townships.[12] Though unaffiliated voters make up most of the district, they tended to vote for the Republican candidates in this area and no Democrat had been elected to the 30th since it was shifted to this area until 2023.[13][14] In the 2001 redistricting, municipalities in the Burlington County portion of the district were removed leaving only the ones on the edge of the county from Bordentown Township and Fieldsboro to New Hanover; Millstone Township was also removed. Added in this redistricting were Washington Township in Mercer County (renamed Robbinsville Township in 2007) and Monmouth's Howell Township and Farmingdale.[15] The 2011 redistricting compacted the district to Lakewood, Wall, and Howell townships, and other shoreline boroughs.[1] As a result of the district shift, incumbent Assemblyman Joseph R. Malone announced his retirement and incumbent 11th district Senator Sean T. Kean dropped down to running for an Assembly seat to avoid a primary fight with Senator Robert Singer.[16][17]
Assemblyman Dave Rible resigned his seat on July 17, 2017, to become Director of the New Jersey Division of Alcoholic Beverage Control.[18] Former Wall Township Mayor Ned Thomson was selected by local Republican committee members as a replacement from a ballot of three candidates, and was sworn in on August 24.[19][20] In 2023, Democrats won an Assembly seat for the first time since 1985 and marked the first time they held any seat from this district since it moved to Monmouth and Ocean counties in 1991.
^O'Brien, Ellen (October 29, 1991). "The Newly Formed 30th District Gets Ready For Its First Election". The Philadelphia Inquirer. Archived from the original on July 21, 2015. Retrieved July 19, 2015. As the 30th District followed New Jersey's population shift south, it slid from mainly Democrat Essex County into a spot on the map where Republicans dominate all three county freeholder boards. Although the voter rolls include only slightly more Republicans than Democrats in the new 30th district, more than half the total number of voters are independents, who often vote for GOP candidates.
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