Tom Petri was elected to the U.S. House in a special election in April 1979 with 50 percent of the vote and won his first full term in 1980. He has been re-elected every two years since.
He was re-elected in 1992 with 53 percent of the vote, defeating Democrat Peg Lautenschlager. He was unopposed in 1994. He was re-elected in 1996 with 73 percent of the vote, defeating Democrat Alver Lindskoog.
Petri was re-elected in 1998 without major party opposition. In 2000, he was re-elected to Congress with 65 percent of the vote and he was unopposed for re-election in 2002.
Petri served in the Wisconsin Senate, 1973-79, and made an unsuccessful bid for the U.S. Senate in 1974.