President Joe Biden and his team remain in damage control mode nearly a week after a disastrous debate performance sparked fears among Democrats that his age and mental acuity could make re-election impossible.

"The president is clear-eyed and he is staying in the race," White House Press Secretary Karine Jean-Pierre told reporters at a heated press conference Wednesday.

"That is what the president is focused on, continuing to deliver for the American people," she said.

His campaign and White House leadership teams called meetings and sent internal memos to staff members as questions continued to swirl around Mr Biden's political future.

White House Chief of Staff Jeff Zients held an all-staff call on Wednesday to quell fears and boost morale.

Mr Biden joined a campaign call on Wednesday to assure staff: "I'm in this race to the end and we're going to win," he said as reported by BBC's US partner CBS News.

Campaign spokeswoman Mia Ehrenberg reiterated to the BBC, “He is absolutely not dropping out."

The next several days will determine whether Mr Biden can ride out panic over his mental fitness or if political headwinds following the 27 June debate will prove too strong.

Top Democrats like Vice-President Kamala Harris and California Governor Gavin Newsom, have said repeatedly that they support the president.

Mr Biden lunched privately with Ms Harris in the White House on Wednesday, according to his public schedule, and also plans to meet with Democratic governors this evening.

Mr Newsom, a top Biden surrogate, is among those attending the meeting. He fielded questions immediately after the debate about whether he would be the party’s nominee, and said he planned to visit Washington to “stand with Joe Biden” and other top Democrats, a spokesman announced on X.

The governor will campaign for Mr Biden in key swing states Michigan and Pennsylvania later this week, according to spokesman Brandon Richards.

Initial polling shows that Mr Biden may have taken a hit from his debate performance.

A fresh New York Times-Siena College poll released today shows that Republican Donald Trump leads Biden 49% to 43% among likely voters. Trump increased his lead by 3 percentage points after the debate.

It is the largest lead for Trump reported by the Times and Siena College since 2015, according to the paper.

Democratic voters are nearly evenly split about whether the president should remain the nominee. The Times-Siena poll found 48% said he should be the nominee, while 47% did not.

A CBS News/YouGov poll similarly found Trump edging slightly ahead of Mr Biden among likely voters after the debate. The survey also revealed a possible enthusiasm gap, with 90% of Republican voters saying they would "definitely" vote compared to 81% of Democrats.

But Democratic lawmakers are voicing concerns about the president's ability to take on the former president in November.

Congressman Lloyd Doggett, a 77-year-old Democrat from Texas, said on Tuesday he was "hopeful" Mr Biden would make the "difficult decision to withdraw."

But former US House Speaker Nancy Pelosi was more circumspect in an MSNBC appearance this week.

"It's going to be up to Joe Biden," she said.

One top Democratic donor told the BBC he felt it was time to move on from Mr Biden.

“I think it’s time for him to pass the torch,” said Ramesh Kapur, a Massachusetts-based Indian-American industrialist who has organised fundraisers since 1988. “ I know he has the drive, but you can’t fight Mother Nature”.

“What I know of him, he will decide what’s good for the country.”

Another mega-donor, who declined to be named, told the BBC he planned to go ahead with a fundraiser for the president later this month at his Virginia home.

He said he got a call from the White House Tuesday letting him know that the president will "stay in the race".

Members of the Democratic National Committee are charged with voting to officially make President Biden the party’s nominee at this August's convention, putting him on the ballot nationwide.

One member, who has spoken to other delegates and requested anonymity to speak frankly about sensitive discussions, told the BBC that the nomination should go to Vice-President Harris if Mr Biden opts not to run.

“If we open up the convention, it will cause pure chaos that will hurt us in November," they said.