John Herbert Adler (August 23, 1959 – April 4, 2011) was a U.S. Representative for New Jersey's 3rd congressional district, serving from 2009 until 2011. He was a member of the Democratic Party. He was formerly a member of the New Jersey Senate from 1992 to 2009, where he represented the 6th Legislative District. The district stretches from the suburbs of Philadelphia to Ocean County.