Longtime Illinois Rep. John Shimkus said Friday he would not seek reelection — becoming at least the 12th House Republican to call it quits after their current term is up.

Shimkus, who was elected in 1996 to represent the 15th District in the southeastern part of the state, made the announcement in an interview Friday with KMOX radio.

His announcement came after Georgia GOP Sen. Johnny Isakson said Wednesday he would retire at the end of the year as he continues battling Parkinson’s disease, setting up two elections for key Senate seats in the Peach State in 2020.

Shimkus was just the latest incumbent Republican lawmaker to not seek re-election.

Others House members leaving include Reps. Rob Woodall of Georgia, Susan Brooks of Indiana, Paul Mitchell of Michigan, Pete Olson of Texas and Martha Roby of Alabama.

Also, Reps. Rob Bishop of Utah; Mike Conaway, Will Hurd and Kenny Marchant of Texas; and Sean Duffy of Wisconsin.

Democratic retirements include Reps. Jose Serrano of New York and Dave Loebsack of Iowa.

Democrats control the House while Republicans hold the Senate, and each party is striving to maintain its majority while trying to flip the chamber they do not control.