John J. Matheussen (born January 30, 1953) is an American Republican Party politician. He served in the New Jersey Senate from 1992 to 2003, where he represented the 4th Legislative District. Born in Jersey City, Matheussen earned his undergraduate degree, a B.A. in Communications, from Seton Hall University. He was awarded a J.D. from the University of Dayton School of Law. In the 1991 Republican landslide in the New Jersey Legislature, Matheussen won an open Senate seat over Assemblyman Anthony S. Marsella, while his running mates George Geist and Mary Virginia Weber won in the Assembly. In the 1991 race, Matheusen took the seat vacated by three-term incumbent Daniel J. Dalton with 51.7% of the vote, with Marsella polling 48.3%. Matheusen won re-election in 1991 over Bernard Lynch by a 5