WASHINGTON (AP) — House Speaker Paul Ryan’s abrupt announcement that he will retire rather than seek another term in Congress as the steady if reluctant wingman for President Donald Trump sent new ripples of uncertainty through a Washington already on edge and a Republican Party bracing for a rough election year.

The Wisconsin Republican cast the decision to end his 20-year career as a personal one — he doesn’t want his children growing up with a “weekend dad” — but it will create a vacuum at both ends of Pennsylvania Avenue. It will leave congressional Republicans without a measured voice to talk Trump away from what some see as damaging impulses, and it will rob Trump of an influential steward to shepherd his more ambitious ideas into legislation.

It’s unusual for a House speaker, third in line to succeed the president, to turn himself into a lame duck, especially so for Ryan, a once-rising GOP star who is only 48 and was the party’s vice presidential candidate in 2012.

His decision fueled fresh doubts about the party’s ability to fend off a Democratic wave, fed by opposition to Trump, in November. And it threw the House into a leadership battle that could end up pushing Ryan aside sooner than he intended and crush any hopes for significant legislation before the election.

Ryan, though, said he had no regrets after having accomplished “a heckuva lot” during his time in a job he never really wanted. He said fellow Republicans have plenty of achievements to run on this fall, including the tax cuts Congress delivered, which have been his personal cause and the centerpiece of his small-government agenda, even though they helped skyrocket projected annual deficits toward $1 trillion.

“I have given this job everything I have,” Ryan said.

Ryan announced his plans at a closed-door meeting of House Republicans. Rep. Mark Walker of North Carolina said an emotional Ryan “choked up a few times trying to get through” his remarks and received three standing ovations.

Still, for many Republicans, it’s unclear who will be left in leadership to counterbalance Trump. Ryan has been “a steady force in contrast to the president’s more mercurial tone,” said Rep. Mark Sanford of South Carolina. “That’s needed.”

The speaker had been heading toward this decision since late last year, said a person familiar with his thinking, but as recently as February he had considered running for another term. His own father died suddenly of a heart attack when he was 16, and though Ryan is in good health, the distance from his family weighed on him. A final decision was made over the two-week congressional recess, which he partly spent on a family vacation in the Czech Republic.

Ryan, from Janesville, Wisconsin, was first elected to Congress in 1998. Along with Reps. Eric Cantor and Kevin McCarthy, he branded himself a rising “Young Gun” in an aging party, a new breed of hard-charging Republican ready to shrink the size of government.

House Majority Leader McCarthy, a Californian known to be tighter with Trump, is expected to again seek the top leadership post that slipped from his reach in 2015. He will likely compete with Majority Whip Steve Scalise of Louisiana.

Ryan’s announcement came as Republicans are bracing for a potential blue wave of voter enthusiasm for Democrats, who need to flip at least 24 GOP-held seats in November to regain the majority.

As the House GOP’s top fundraiser, Ryan’s lame-duck status could send shockwaves through donor circles that are relying on his leadership at the helm of the House majority. He has hauled in $54 million so far this election cycle.

In Wisconsin, Republicans had no obvious successor in waiting. The most likely GOP candidate for Ryan’s seat is state Assembly Speaker Robin Vos, Republicans in the state said. Another Republican mentioned as a potential candidate is longtime Ryan family friend and backer Bryan Steil, an attorney and member of the University of Wisconsin Board of Regents.