District 21 encompasses 16 communities in Morris, Somerset and Union counties: Berkeley Heights, Bernards, Chatham Borough, Cranford, Far Hills, Garwood, Kenilworth, Long Hill, Mountainside, New Providence, Roselle Park, Springfield, Summit, Warren, Watchung and Westfield.
Voter registration is 25 percent Democratic and 28 percent Republican, with the most of the rest unaffiliated.
Both GOP incumbents are on the ballot. Assemblyman Jon Bramnick of Westfield is an attorney who has served in the lower house since 2003 and also served on the Plainfield City Council in the 1980s. Assemblywoman Nancy Munoz of Summit was first elected in 2009.