A number of major Democratic donors have publicly warned they will withdraw their funds if Joe Biden will not be replaced as the party's candidate after his disastrous performance in last week's debate, reported the "BBC".
Friday is a big day for the US president as he tries to shore up his candidacy with a rare prime-time TV interview and a rally in Wisconsin.
Pressure on Biden, 81, to step down grew after a debate marked by several instances where he lost his train of thought.
Although Biden conceded his defeat in the debate, he vowed to remain the Democratic nominee to face Donald Trump in the November presidential election.
Biden's public appearances have significantly decreased since the debate, notes "BBC".
In a speech at the White House to military families on Thursday to mark Independence Day on July 4, he stumbled over his words, calling Trump "one of our colleagues, a former president".
And in an interview with WURD radio in Philadelphia, he lost his train of thought and said he was proud to be the first black woman to serve with a black president.
Donors are currently weighing their options, Abigail Disney, heiress to the Disney family fortune, told the business news channel CNBC, stressing that she does not believe Biden can win against Trump.
She said her intention to withdraw her support was rooted in "realism, not disrespect.
"Biden is a good man and has served his country admirably, but the stakes are too high."
The consequences of a defeat in November "would be really terrible,", she added.
Philanthropist Gideon Stein told the New York Times that his family would withhold $3.5 million from nonprofits and political organizations active in the presidential race if Biden does not withdraw.
Hollywood producer Damon Lindelof, who has donated more than $100,000 to Democrats this election cycle, wrote a public essay in Deadline urging other donors to withhold their funds until change occurs.
The brother of Barack Obama's former chief of staff, Ari Emanuel, told a conference in Colorado that the funding freeze was the key to Biden's withdrawal from the race, the Financial Times reported Thursday.
"The lifeblood of a campaign is money, and perhaps the only way. . . is if the money starts to dry up"
Ramesh Kapoor, a Massachusetts-based Indian-American industrialist, has been a fundraiser for Democrats since 1988
"I think it's time for him to pass the torch," Kapoor told the BBC this week. "I know he has incentive, but you can't fight Mother Nature."
Biden's campaign said it raised $38 million from debate day through the weekend, mostly through small donations -- and a total of $127 million in June alone.
They acknowledged he had a tough debate, but said he was ready to show the public he had the stamina to campaign.
But the president faces a series of negative polls that suggest his Republican challenger's lead has widened since the Atlanta debate.
A New York Times poll released Wednesday showed Trump now holding his largest lead ever of six points.