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Illinois Republican John Shimkus said in a statement Friday afternoon that he will not seek reelection in 2020, joining 10 other House Republicans who have announced that they will head for the exits.

“As Illinois candidates begin to circulate petitions next week, now is the time for me to announce that I will not be seeking reelection,” Shimkus wrote. He has been in Congress since 1997.

“It has been the honor of my lifetime to be asked by the people of Illinois to represent them in our nation’s capitol,” Shimkus added. “I will leave the political field knowing that I have served honorably and, with the help of many, accomplished a lot for my constituents, our state, and our nation.”

Rep. Rodney Davis, an Illinois Republican who worked in Shimkus’ congressional office before running for the House himself, said on KMOX radio’s “Mark Reardon Show” on Friday that Shimkus’ departure will have an impact on the GOP conference and its institutional knowledge.

“This is a guy who people will go to for advice,” Davis said. “The leadership goes to John for advice on stuff.”

“We’re grateful for you, buddy,” he added.

On the same radio show, Shimkus said he hadn’t informed the White House or members of the GOP conference leadership about his plans to leave, although Republican Whip Steve Scalise of Louisiana and Ways and Means Committee ranking member Rep. Kevin Brady of Texas – Shimkus’ townhouse roommates in DC – knew about it in advance.

Shimkus is a senior member of the House Energy and Commerce Committee and is the top Republican on its Environment and Climate Change Subcommittee.

In 2018, he won reelection in Illinois’$2 15th Congressional District with more than 70% of the vote.

He has also represented Illinois’$2 19th and 20th congressional districts. The 20th District was disbanded when Illinois lost a congressional seat after the 2000 census, at which point Shimkus ran for the new 19th District, which included much of his old district. After the 2010 census, the 19th District was also disbanded and Shimkus ran in the redistricted 15th District.

His announcement comes the same week that Republican Rep. Sean Duffy of Wisconsin said he would step down from Congress in September to spend more time with his family ahead of the birth of his ninth child.

Other House Republicans who have recently decided not to seek reelection are Reps. Rob Woodall of Georgia, Susan Brooks of Indiana, Paul Mitchell of Michigan, Martha Roby of Alabama, Rob Bishop of Utah and Pete Olson, Mike Conaway, Will Hurd and Kenny Marchant, all of Texas.

This story has been updated.