Santos Is Out of Congress. Republicans Still Face Deep Divisions.

Moments after House members cast a historic vote to expel Representative George Santos of New York, Speaker Mike Johnson banged the gavel with a grim look on his face.

“In light of the expulsion of the gentleman from New York, Mr. Santos, the whole number of the House is now 434,” he announced gravely to an uncommonly silent House chamber, looking down with a faint grimace.

It made official what had been apparent in recent days — that many of his fellow Republicans had been willing to defy his wish to keep Mr. Santos, a serial fabulist, in Congress, and that Mr. Johnson and his party were now facing ever-more brutal political math. Their slim four-vote majority has dwindled to just three.

That will make governing more difficult for Republicans, who have already had immense trouble corralling their fractious members to steer legislation through the closely divided House. A pair of government funding deadlines early next year will test Mr. Johnson’s ability to maneuver with even less wiggle room in his party than before to navigate a pending shutdown and keep his job.

It was also a rare feat to address an obvious wrong by a chamber that has distinguished itself this year mostly by paralysis and dysfunction in the face of crisis.

The ouster of Mr. Santos came in a Congress marked by extraordinary levels of chaos. The disarray was in full effect almost from the first day in January, when Representative Kevin McCarthy, Republican of California, engaged in the longest-ever fight to win the speakership. It continued in October with his becoming the first speaker in history to be removed from the job. And it has featured multiple Republican mutinies on the floor that have paralyzed legislative business and put the party’s divides on vivid display.

With the 118th Congress on pace to pass the fewest bills of any Congress in decades, some House Republicans have begun describing the state of their party as an international embarrassment.

Through it all, Mr. Santos has been his own symbol of chaos. After The New York Times revealed Mr. Santos’s myriad lies about his biography and federal investigators accused him of multiple crimes, his fellow Republicans protected him.

But in the end, it was Republicans’ raw political interest that was Mr. Santos’s undoing, even though it left them with an immediate math problem. Having concluded that allowing Mr. Santos to seek re-election would cost Republicans a competitive congressional seat — and hurt their chances of holding the majority — Mr. McCarthy urged on a House Ethics Committee investigation into his conduct that was more aggressive and public than is traditionally the case.

The result was a scathing Ethics Committee report. Many Republicans ultimately calculated that the clear evidence of Mr. Santos’s lies and fraud was more damaging to the party than the value of his single vote. Nearly half of them voted on Friday to expel him. Several argued that Mr. Santos was too much of a drag on the Republican brand in New York and that it would be easier for the party to win the seat in the next election without him in it.

Since the Civil War, no member of Congress had been expelled without a criminal conviction. But members of the ethics panel argued a new standard could be set: A damning bipartisan report from the committee could be grounds enough for expulsion.

“To me, it was a pretty easy vote to remove because there was a unanimous recommendation out of the Ethics Committee,” said Representative Tom Cole of Oklahoma, the chairman of the Rules Committee who is known as an institutionalist and a leadership ally. “I have a lot of faith in those people. There’s no dissent there.”

Mr. Cole also acknowledged the tough political math for Republicans, who in January and February will attempt to broker two different spending deals to keep the government open. New York will not be able to have filled Mr. Santos’s seat by then through a special election.

Mr. Santos’s removal means that Mr. Johnson can lose only three Republican votes on any piece of legislation to the Democrats if all in the chamber are present and voting. Another Republican, Representative Bill Johnson of Ohio, announced he would leave Congress in the coming months to become the president of Youngstown State University in Ohio.

Mr. Cole said he was not happy about voting for his party to lose a precious vote.

“I prefer not to do that, but in this case, I think you need to do what the institution demands,” Mr. Cole said.

Representative Michael Guest, Republican of Mississippi and the Ethics Committee chairman, said he appreciated that Mr. Johnson did not pressure members to save Mr. Santos even as he made clear early in the week he had deep reservations about removing the New Yorker.

“I do applaud leadership for not whipping against this vote and trying to protect Mr. Santos and keep him in the House of Representatives, just to protect our very narrow majority,” Mr. Guest said.

Still, several members said they were worried about retribution, and starting a new cycle of payback. Already, actions like impeachment attempts, censure and removing a member from committees — once exceedingly rare — have become more common and embroiled in cycles of pettiness, politics and spite.

Even on his way out, Mr. Santos attempted to bring a resolution to expel another New York lawmaker, Representative Jamaal Bowman, a Democrat who pleaded guilty to pulling a fire alarm in a House office building.

“We’ve been lectured to politically for the last four years, a lot of it in the press, about our institutions. What happened here today goes against the principles of our institutions,” said Representative Byron Donalds, Republican of Florida, who voted to save Mr. Santos. He dared lawmakers to oust a Democratic senator who is also under indictment as payback: “Bring the articles for Bob Menendez in the Senate,” he said.

Representative Glenn F. Ivey, Democrat of Maryland and a member of the Ethics Committee, said he had already noticed an uptick in complaints coming into the panel that seemed personal and partisan.

“We’re getting stuff coming through that does look like it’s really not up to the standards of what should be coming to us,” Mr. Ivey said. “The tit-for-tat kind of stuff, we have to be careful about.”

Still, he said he was proud of the work of the committee, which over many decades has earned a reputation for fecklessness and secrecy.

“This breadth of misconduct is really pretty astonishing,” Mr. Ivey said of Mr. Santos. “The Ethics Committee, the view had become that we’re basically a toothless tiger. This is where legitimate complaints went to die. And I hope this changes that, and makes it clear, not only to the American people but to ourselves, that we really are policing ourselves.”