There has been a concerted effort by a growing number of Democrats to convince President Joe Biden to drop his bid for re-election following his horrendously bad performance at last week's debate against former President Donald Trump.

That effort now includes major Democratic donors threatening to withhold their money from his campaign and the party more broadly unless or until Biden pulls out of the presidential race and is replaced as the nominee, CNBC reported.

Biden has thus far stood defiant and refused to quit his run for a second term in the face of mounting criticism and panic over his debate performance that fully exposed the extent of his physical and cognitive decline.

Donors halt funding for Biden campaign

CNBC reported that Abigail Disney, heir to the family fortune and a prominent longtime Democratic donor, revealed on Thursday that she will no longer contribute any funds to the party she has financially supported for years unless President Biden exits the 2024 race.

"I intend to stop any contributions to the party unless and until they replace Biden at the top of the ticket," Disney said. "This is realism, not disrespect. Biden is a good man and has served his country admirably, but the stakes are far too high."

"If Biden does not step down the Democrats will lose. Of that I am absolutely certain. The consequences for the loss will be genuinely dire," she added.

Taking a similar approach as Disney is wealthy entrepreneur and philanthropist Gideon Stein, who told CNBC, "Joe Biden has been a very effective president, but unless he steps aside my family and I are pausing on more than $3 million in planned donations to nonprofits and political organizations aligned with the presidential race, with the exception of some down-ballot work."

"Virtually every major donor I've talked to believes that we need a new candidate in order to defeat Donald Trump," he added.

Donors pressuring Biden to drop out

Nor are Disney and Stein alone in planning to withhold their donations to force a change at the top of the Democratic ticket, as The New York Times reported on the growing number of "major Democratic donors" who are devising various plans to pressure President Biden to drop out of the race.

Some of those plans involve withholding all funds from the Biden campaign and the Democratic party while others have only cut off the campaign but continue to contribute to Democratic candidates in Congress and at the state level.

Another plan involves the creation of a new super PAC that intends to raise upwards of $100 million to either bolster a replacement nominee or fund down-ballot races only if Biden maintains his candidacy.

"This is something unique," said longtime Democratic strategist James Carville, who just days earlier urged major Democratic donors to withhold all funds from any Democratic candidate or group who refused to get on board with the movement to replace Biden as the party's nominee.

Trump now leads in fundraising, polling

The cutting off of funding for President Biden's re-election campaign comes at a crucial time as it, after enjoying an initial substantial fundraising advantage, was just eclipsed last month by the Trump campaign in terms of total funds raised monthly and quarterly and in terms of available cash on hand, according to Bloomberg News.

It also comes as polling shows a sharp post-debate decline in voter support for Biden paired with a notable and simultaneous uptick in support for Trump just four months ahead of the election.