Rep. Pat Ryan has joined the small list of House Democrats asking President Joe Biden to step aside – becoming the first New Yorker in Congress to do so publicly.

“Trump is an existential threat to American democracy; it is our duty to put forward the strongest candidate against him,” Ryan wrote on X, formerly known as Twitter, on Wednesday. “Joe Biden is a patriot but is no longer the best candidate to defeat Trump.”

“For the good of our country, I am asking Joe Biden to step aside -- to deliver on his promise to be a bridge to a new generation of leaders,” Ryan said.

Ryan was first elected in a special election in 2022. He is running for re-election in New York’s competitive 18^th District, where he faces a challenge from Republican Alison Esposito.

In a statement, Esposito criticized Ryan’s call for Biden to drop out, saying, "Pat Ryan could have raised alarms years ago when Joe Biden's mental acuity was first put in question. Once again, Pat Ryan refuses to lead from the front … Pat Ryan only makes decisions that are politically expedient for him.”

Ryan’s plea comes amid mounting concern that Biden could be an anchor on down-ballot races, including in New York, where the fate of competitive congressional seats like Ryan’s Hudson Valley district hang in the balance, potentially determining which party controls the U.S. House next year.

In a social media post Wednesday, Bronx Congressman Ritchie Torres wrote, “In determining how to proceed as a party, there must be a serious reckoning with the down-ballot effect of whomever we nominate. What matters is not how we feel but what the numbers tell us.”

Those concerns are just part of what House Democratic Leader Hakeem Jeffries and Senate Majority Leader Chuck Schumer have heard behind closed doors in recent days, as they hosted listening sessions with their Democratic colleagues.

“My conversations right now are focused on the caucus and making sure that everyone has the opportunity to be heard,” Jeffries told reporters Wednesday.

So far, the two Brooklynites, who have risen to the peak of Democratic power in their respective chambers, are backing Biden. On Tuesday, facing questions about the president’s ability to win in November and serve four more years, Schumer repeatedly offered the same refrain: “I’m with Joe.”

But with concerns over Biden’s candidacy continuing to percolate on Capitol Hill, how these two leaders navigate questions over Biden’s future could be legacy-defining.

“History is written by the winners,” said Casey Burgat, who leads the legislative affairs program at The George Washington University. “If you back a losing horse, and you have a lot of members of your caucus telling you that this is a losing horse - if you back that losing horse, it is very, very tough to go back to those same members and say, ‘Hey, trust me, and again, I'll get the next one, right.’”

Jeffries is expected to relay his findings from his listening sessions to the president. Meanwhile, on Thursday, Biden is poised to host a solo press conference – a chance to potentially reassure colleagues about his fitness for office after his debate performance two weeks ago or raise additional concerns about his candidacy.