He was first elected to the 21st District of the Assembly (South Milwaukee, Oak Creek and a small portion of Cudahy) in a March 1996 special election, with 6758 votes to 5609 for Republican Mike McCarrier; and was reelected in November 1996 with 14,020 votes to 6544 for Republican Arden Degner.

[5] Plale won a three-way Democratic primary, and a general election in which he polled 5282 votes to 2199 for Green Jim Carpenter (the Republicans did not contest the seat).

[7] He lost his 2010 bid for re-nomination on September 14, 2010, when he was defeated in the Wisconsin Democratic primary election by Chris Larson, a member of the Milwaukee County Board of Supervisors,[8] who contended that Plale was too conservative.

[10] Larson subsequently won the Senate race, in an election that saw four Democratic seats fall to Republicans.

After the vote, Plale was appointed administrator of state facilities in January, and later as Wisconsin Railroad Commissioner, by Governor Scott Walker, also a Republican.