House Minority Leader Nancy Pelosi (D-Calif.) speaks during her weekly news conference on Capitol Hill on Nov. 15, 2018. (Yuri Gripas/Reuters)

A House Democrat who signed a letter this week declaring his opposition to Rep. Nancy Pelosi as speaker reversed course Wednesday and said he would support her as Democrats enter the majority next year.

Rep. Brian Higgins of New York said he had changed his mind after securing an “agreement in principle” that Democrats would undertake a “serious good faith effort” to advance legislation lowering the Medicare eligibility age to 50 as well as a trillion-dollar infrastructure blitz.

Until Wednesday, Higgins had been an outspoken critic of Pelosi, telling reporters that she represented a serious obstacle for Democrats running in Republican-leaning districts. But he said in an interview Wednesday that he had come to terms after discussions with Pelosi as well as with Senate Minority Leader Charles E. Schumer (D-N.Y.) and Rep. Richard E. Neal (D-Mass.), the incoming chairman of the Ways and Means Committee.

“There’s no alternative right now and there’s not going to be one,” he said. “And in the event this breaks down on the floor, somebody could grab the speakership that really doesn’t deserve it.”

In a statement, Pelosi praised Higgins as “an extraordinary leader on the issue of achieving quality, affordable health care for all Americans” and said his proposal to allow Americans as young as 50 to “buy in” to Medicare is “central to this debate, as we work to build on the Affordable Care Act.”

Pelosi picked up additional endorsements Wednesday from newly elected Reps. Alexandria Ocasio-Cortez (D-N.Y.) and Lauren Underwood (D-Ill.). Ocasio-Cortez’s nod was especially significant given her emergence as a young star of the political left after defeating longtime incumbent Rep. Joseph Crowley (D-N.Y.) in a June primary.

In a tweet, Ocasio-Cortez dismissed Pelosi’s opposition as an “apparent effort to make the party even more conservative and bent toward corporate interests.”

“So long as Leader Pelosi remains the most progressive candidate for Speaker, she can count on my support,” she wrote.

Higgins, who represents a Buffalo-area district and sits on the coveted Ways and Means panel, said he was not threatened in any way for his opposition and called his conversations with Pelosi and Schumer “highly professional.”

His change of heart comes a day after Pelosi won the support of another Democratic critic, Rep. Marcia L. Fudge of Ohio, who had been considering a run for speaker herself. Fudge said she had secured a more prominent role in leadership decisions for African American women as well as the chairmanship of a subcommittee on elections.

That leaves 15 Democrats who have signed a letter vowing to oppose Pelosi, with another four who have said in statements that they oppose her. Currently Democrats are on track to enjoy a 16-seat majority, though that number could grow as several uncalled races are settled.

Pelosi will need to win a majority of House members when a floor vote is called on Jan. 3.

Higgins had previously criticized Pelosi’s unwillingness to move on from leadership after 16 years in the top role but softened his criticism Wednesday, saying she “is not going to give a date specific” for her departure.

“I don’t think that’s realistic given the fact that the House needs all the leverage it can muster,” he said.