– President Donald Trump’s margin of support — among the American people and in Congress — was already thin. After Tuesday’s defeat in Alabama, it is decidedly thinner, more than the loss of one Republican senator’s vote would suggest.

The win by Democrat Doug Jones over Republican Roy Moore in one of the nation’s reddest states demonstrated both the limits of Trump’s power to help the Republican Party in key congressional races and the potential for Democrats to rally voters against one of the least popular presidents in modern history.

It will also mean Republicans have one less vote to spare in the Senate, where a 51-49 majority will make passing major legislation even more difficult than it has been in Trump’s rocky first year, absent compromises with emboldened Democrats.

Those Republicans who remain will have more motivation and leverage to decide what’s best for their own political futures, rather than Trump’s, prompting more of them to buck the president or demand major concessions.

Trump on Wednesday dismissed criticism that he had backed a flawed candidate, and instead blamed Republicans who spurned Moore after accusations that he had preyed on teenage girls decades ago as a young county prosecutor in his 30s.

Meeting reporters ahead of a lunch with Republicans, Trump arched his eyebrows and shrugged his shoulders in apparent frustration as he renewed his argument that concerns about Moore’s character were outweighed by the need for his vote in the Senate.

But he acknowledged that some Republicans disagreed. “Wish we would have gotten the seat,” Trump said. “A lot of Republicans feel differently. They’re very happy with the way it turned out.”

But, he added, “as the leader of the party, I would have liked to have had the seat. I want to endorse the people that are running.”

Trump and Senate Majority Leader Mitch McConnell are hoping to wrap up their tax cut legislation before Jones is sworn in. Yet even the tax vote is uncertain in the election’s wake.

Democrats are demanding that Jones be seated before a final tax vote. They are using the arguments McConnell used in the past to block Democrats from voting on President Barack Obama’s Supreme Court nominee, Merrick Garland — that the voters’ choice should have an opportunity to weigh in on major decisions. McConnell blocked a vote on Garland for most of a year, arguing that the Senate should wait for a new president.

Even if McConnell ignores Democratic demands, as is likely, he and Trump will have to close the deal with House Republicans on a bill that is unpopular with voters, adding to the caution of wavering Senate Republicans. Holdouts such as Susan Collins of Maine, Bob Corker of Tennessee and Marco Rubio of Florida could demand more concessions for their support, possibly delaying final action into the new year, when Jones is seated.

The new political reality could also complicate negotiations over immigration and an essential bill to fund the government and keep it open beyond the holidays.

Senate Minority Leader Chuck Schumer, a New York Democrat, said he hoped Republicans would “hear the lessons” of the election as he reeled off issues on which Democrats would pitch a fight, including on programs for veterans, opioid addiction and pensions.

Republicans will have to grapple with the political weaknesses exposed by the Moore loss at least through next year’s midterm election campaigns if not beyond. Turnout was notably down among rural voters in conservative, white parts of Alabama, areas where Trump is strongest. Democrats were far more motivated, especially in counties with large black populations and in suburbs.

For Trump, it was a third consecutive loss, further undermining his aura of influence among Republican voters.

He had first endorsed Luther Strange, the senator appointed to fill the seat Jeff Sessions left to become Trump’s attorney general. When Moore beat Strange in the Republican primary, Trump then endorsed Moore.

Yet Trump, as he typically does, worked to escape blame — with a tweet. “The reason I originally endorsed Luther Strange (and his numbers went up mightily), is that I said Roy Moore will not be able to win the General Election,” Trump wrote. “I was right!”

Despite his losses, Trump can look to his past Democratic predecessors for precedents suggesting even big setbacks aren’t fatal.

Presidents Bill Clinton and Obama both suffered devastating congressional losses in their first midterm elections — Clinton saw Democrats lose majorities in both the House and Senate, and Obama in the House — only to recover and win re-election two years later.

Neither president subsequently enjoyed legislative success as great as in their first year. Jim Manley, a former Democratic Senate aide, said the loss “makes efforts to pass what’s left of [Republicans’] agenda that much tougher.”

Moore’s loss leaves a target on former Trump adviser Steve Bannon, who urged Trump to back Moore and stumped for him. “GOP must do right thing and DUMP Steve Bannon,” Rep. Peter King, R-N.Y., tweeted. “His act is tired, inane and morally vacuous.”