The 2021 New Jersey State Senate election was held on November 2, 2021. New Jersey voters elected state senators in all of the state's legislative districts for a two-year term to the New Jersey Senate. This was the first election since 1991 where Republicans net gained state Senate seats. Democrats would later be restored to 25 seats following the party switch of Samuel D. Thompson in 2023.

Jon M. Bramnick is an American Republican Party politician and comedian, who has served in the New Jersey Senate since 2022, representing the 21st legislative district. He previously served in the New Jersey General Assembly, representing the 21st Legislative District from 2003 to 2022, where he was the Assembly Republican Leader from January 2012 to January 2022. He was appointed to the Assembly in 2003 to fill the unexpired term of the vacancy created upon the selection of Thomas Kean Jr. to fill an unexpired New Jersey Senate term. He was elected to a full two-year term later that year and was re-elected in 2005, 2007, 2009, 2011, 2013, 2015, 2017, and 2019. He was elected to the New Jersey Senate in 2021 and was re-elected in 2023. In January 2024, Bramnick announced he was running for Governor of New Jersey in 2025.