President Biden found himself in a growing political crisis Wednesday as Democrats on Capitol Hill, the high-dollar donor community and even members of his own senior team became increasingly vocal about his muted response to concerns about his viability as the party’s standard-bearer after Thursday’s shaky debate.

The growing worry comes as Biden has told allies in recent days that he is in a tough moment and that he has to prove to voters in the coming days that he is up for the job, according to two people familiar with the conversations. His critics inside the senior ranks of the party argue he has done little over six days since the debate to directly address the deep concerns of Democrats and the voting public about his ability to handle the job.

Biden has only appeared in public three times since a rally Friday in North Carolina — for remarks on a Supreme Court decision, on extreme weather and at Stonewall National Monument in New York — to speak for a total of 22 minutes, exclusively while using teleprompters. He also attended a series of fundraisers and other weekend campaign events.

One senior campaign adviser called the situation “a deafening silence,” from the top, reflecting the concerns of other advisers who described a failure of the president to publicly demonstrate his fitness for office as panic built inside the party. Other longtime Biden allies — who like others spoke on the condition of anonymity to speak frankly — have described continued frustration about the political response and a growing conviction that a change needs to be made.

Biden spent much of Wednesday trying to push back on the concern by calling congressional leaders who had not heard from him, addressing his campaign staff and doing interviews with a series of Black radio stations ahead of a planned meeting with Democratic governors.

“The past few days have been tough. I’m sure you’re getting a lot of calls, and I’m sure many of you have questions as well," Biden told campaign staffers in a conference call, according to a person familiar with the remarks. “Let me say this as clearly as I possibly can and as simply and straightforward as I can: I am running. I’m the nominee of the Democratic Party. No one’s pushing me out. I’m not leaving. I’m in this race to the end, and we’re going to win because when Democrats unite, we always win.”

Vice President Harris, who was also on the call, added: “We will not back down. We will follow our president’s lead. We will fight, and we will win.”

Even those who still argue Biden remains the best candidate admitted lost ground in recent days, though hope remains that poll numbers will stabilize over the coming week. Some Democrats have begun openly considering the idea that Harris could replace Biden on the ticket to take on Republican Donald Trump in November.

“There is significant erosion among elected [officials] and donors,” said Dmitri Mehlhorn, a donor adviser working with outside groups to elect Biden. “But the elected and the donors do not represent the substantial part of swing voters who are in the battleground states.”

Biden’s campaign team insisted on a June debate with Trump to address voter apathy and concerns about Biden’s age. His stammering performance, instead, triggered alarm in the party and an increase in public concern about his competence, as measured by public polls.

Biden’s private outreach to lawmakers has also been minimal since the debate, prompting leaders within the party to express their surprise to others. Biden waited until Tuesday to speak with House Democratic leader Hakeem Jeffries (N.Y.) and until Wednesday morning to speak with Senate Majority Leader Charles E. Schumer (N.Y.) and former House speaker Nancy Pelosi (Calif.). His meeting Wednesday afternoon with Democratic governors was scheduled only after a request by Wisconsin Gov. Tim Walz.

Some House Democrats continued to debate among themselves Wednesday whether to call on Biden to step down, with drafts of a possible public letter circulating. Two Democratic members of Congress — Jared Golden (Maine) and Marie Gluesenkamp Perez (Wash.) — publicly said Tuesday that Biden can no longer win, while Rep. Lloyd Doggett (Texas) said he should be replaced as the party’s presidential candidate.

On a text chain Wednesday morning, House members shared a new YouGov poll that showed Biden down two points to Trump. Another poll shared on the text chain showed that former first lady Michelle Obama would trounce Trump by 10 points.

The anxious lawmakers didn’t put any stock in the numbers but marveled at how “there’s all this potential to defeat Trump and it also says how much it’s being held back by Biden,” according to one lawmaker on the text chain.

Rep. James E. Clyburn (D-S.C.), one of Biden’s closest allies in the House, said Wednesday morning that he had still not spoken with the president. A spokesperson said the two connected later in the day.

“I think that the president should have a series town hall-type meetings, engaging with voters, with the media,” Clyburn said. “I think he should not have his reactions to questions from the voters through a filter. Let him give unfiltered responses to their questions, and let the media report on it.”

Democrats involved in House and Senate races say much will depend on whether Biden’s polling continues to slide in coming days, and how that impacts Democratic candidates. There are some signs Republicans are moving to capitalize on Biden’s faltering debate performance. Arizona’s Republican Senate candidate Kari Lake plans to air a statewide ad that hits Democratic candidate Ruben Gallego on Biden’s decline, said one person familiar with the ad planning.

Biden advisers pointed to a coming schedule of events that could begin to address these concerns, including campaign travel Friday to Wisconsin and Sunday to Pennsylvania. He has a scheduled sit-down interview Friday with ABC News.

Both the campaign and the White House are hoping that a series of events in the days after the Fourth of July holiday will reassure voters and party insiders. They point out that no senior Democrats have called on him to step down.

The initial damage control after Thursday’s debate and the subsequent North Carolina rally was handled almost entirely by staff. Those private phone calls, video conferences and other presentations focused largely on other aspects of the campaign and offered no opportunity for questions or only screened questions. Top campaign staff have written multiple memos and emails to staff, donors and supporters asking for calm and redoubled work.

“The president and his team have been through the highest of highs and the lowest of lows. And you know what? That will continue,” Jeff Zients, the White House chief of staff, said on the White House call. “The only way to get through it is as a team.” He took no questions.

The encouraging talk about fundraising numbers and the grass-roots operation has failed to address the central concern that Biden himself is not up for the job, say several senior strategists who have decided in recent days that either Biden has to prove his ability or that Democrats need a new nominee. Allies have also pointed out that the focus on internal campaign polling and analytics — showing a stable race, with Biden trailing Trump slightly — has failed to address the question of how the debate performance affected Biden’s ability to overtake Trump before the fall.

The argument by top Biden advisers has long been that enough voters will ultimately choose to oppose Trump, but that argument lacks a clear empirical basis beyond polls that show a majority of the country remains open to supporting Biden in theory, people familiar with the situation said. The campaign has also been hit by external polling that has shown a sharper drop from Biden’s already poor standing in matchups with Trump and third-party candidates.

“'The polling isn’t changing’ is not a sufficient message,” said one Democratic veteran of presidential efforts, who reflected the sentiment of several other strategists. “The fundamental point is it is not about a single debate performance. It is about the shaky confidence that people had is now gone. And him giving two four-minute statements and reading a teleprompter at a rally and a fundraiser is not going to cut it.”

The high-dollar donor community, meanwhile, has overwhelmingly turned against Biden, according to people familiar with the conversations. Whether that has a material effect on fundraising if Biden stays in the race is less clear. In multiple cases, donor advisers say, large donations to outside groups that were expected have been withheld since the debate.

Liberal donor networks like the Democracy Alliance, American Bridge and the Strategic Victory Fund have all held calls in recent days where donors have expressed concerns about moving forward, though none of the calls resulted in formal calls for Biden to leave the race. Officials at one independent group has begun to review polling to see how their planned advertising will fare if Biden is not the nominee.

Multiple donors have described the debate performance as reflecting elements of Biden’s performance in smaller group settings at donor events in recent months, when he appeared halting and struggled to communicate. That recognition has fueled calls for him to step aside, according to people familiar with those conversations.

A business executive who helped arrange a fundraiser for the Chicago convention in the last year said the Biden team refused to let even major donors ask questions in a small group. That was shocking, this person said.

“I told them my donors don’t care about a photo. They want to talk to him. The Biden people just wouldn’t let them,” the person said. “It was clear they were managing him in a way I’ve never experienced before. Donors expect to get to talk to the president if you’re writing a big check and having an event with him.”

Multiple top party donors joined the chorus on Tuesday in phone conversations with Pelosi and Schumer to say that the current situation was not sustainable and a new nominee was needed, according to people familiar with the call. Spokespeople for Pelosi and Schumer declined to comment.

During a fundraiser in McLean on Tuesday night, he was in good spirits and spoke at a donor event without a teleprompter set up for the first time since the debate. He made light of his debate struggles — “I know I didn’t have my best debate nights” and suggested it was a result of jet lag. Biden returned to the United States from meetings in Europe 12 days before the debate.

Biden touted strong campaign fundraising since the debate. “So far, so good,” he said.

Members of Biden’s family have been firm in encouraging him to stay in the race, adamantly saying that he has a game plan and rebuffing suggestions that he would consider stepping aside, according to four people close to the family. “The family is still all-in,” one of them said, speaking on the condition of anonymity. “They’re still supportive.”

They have acknowledged the tough debate, and the tenuous moment, but have said absent high-level defections like Pelosi or Schumer, or a significant drop in polling data, he will remain as the party’s nominee. They also frequently point to others having often doubted him only for him to overcome expectations, a sentiment still coursing through many of the family members, the people said.

Josh Dawsey, Liz Goodwin, Paul Kane and Yvonne Wingett Sanchez contributed to this report.