He likened the opportunity to a minor league baseball player being offered the opportunity to play in the majors.

“Who would not say, 'No I don’t want to go’?” Shimkus said.

A total of 19 House Republicans, including Shimkus, have decided to call it quits this cycle, a sign of how difficult it will be for the GOP to win back the majority in what’s already shaping up as a tough election season.

Last month, when Shimkus was still expected to retire, he drew national attention when he took his name off the Trump campaign’s list of supporters over disagreements on Syria policy. But on Tuesday, he made clear he strongly supports the president’s domestic agenda despite occasional disagreements on international policy.

“I’ve always struggled with the president’s isolationist bent,” he said. “I have a policy difference — one or two — but judges, life, tax relief, regulatory burden. I mean, it’s an easy choice against a socialist.”

Shimkus is the most senior Republican on the Energy and Commerce Committee after Rep. Fred Upton of Michigan, who is term-limited from seeking the top Republican spot on the powerful panel with jurisdiction over energy, climate change, health care, the internet and product safety issues.

Walden’s retirement has set off a scramble among Republicans on the committee: Reps. Michael Burgess of Texas, Cathy McMorris Rodgers of Washington, Bob Latta of Ohio and Brett Guthrie of Kentucky all expressed interest in the position Monday after Walden’s retirement announcement. If Shimkus threw his hat into the ring, he would likely be an immediate front-runner, given his seniority status and ties to leadership.

Shimkus, who was first elected to Congress in 1997, represents a heavily Republican district in southeastern Illinois: Trump won 70 percent of the district in 2016. His rebuke of Trump over Syria could come back to haunt him in a primary bid.

Shimkus still has $1.1 million cash on hand that he could use toward his reelection bid, according to his most recent filings and the Center for Responsive Politics.

But Shimkus pointed out that he would need to get a petition signed in order to get on the ballot by the December deadline and acknowledged that could be a challenge.

“Right now, I have no petition, no circulators,” he said. “I’ve closed my campaign office.”

