Democratic alarm over Joe Biden's widely-panned debate performance Thursday night quickly spread through the party's donor class, increasing the uphill climb facing the president in the race for dollars this summer.

Biden previously lost the fundraising battle with Donald Trump in both April and May and had less cash in the bank at the beginning of this month.

The president's campaign is aiming to change that with a fundraising swing that begins this evening with a campaign reception in Manhattan. He is then scheduled to travel to the wealthy Hamptons enclave this weekend for more events before a fundraising deadline at the end of the month.

But the debate performance raised a new wave of doubts among those who fund the president. Many Democrats and other political observers are even asking if Biden will stay on the ticket at all, with the president insisting he's not going anywhere.

One indication of the newly-wary donor mood came from the camp of Reid Hoffman. The billionaire co-founder of LinkedIn has been Biden's No. 1 individual donor, according to early campaign finance filings.

On Thursday evening, under a subject heading asking “what just happened," a top Hoffman adviser used a note sent to Hoffman's network of friends and allies to offer assurance while also acknowledging what was obvious to many about Biden's debate performance.

"Joe had a horrible night, cementing concerns about his age, his greatest electoral weakness," said the note reviewed by Yahoo Finance.

"Our odds of Trumpocalypse II just materially increased," the adviser added, while also cautioning the recipients to "take a deep breath."

The president on Thursday night repeatedly offer hard-to-follow answers in the face of broadside after broadside from Trump. In one moment, Biden appeared to lose his train of thought completely, playing directly into voter concerns about his fitness for office.

Further challenges

In addition to his problems with high-dollar donors, Biden could also face new challenges with grassroots givers.

Many of the party faithful reacted Thursday night with a wave of unease for their candidate.

The Biden campaign organized numerous official campaign watch parties Thursday night — events that often double as opportunities to sign up new donors — with report after report of unhappy audiences at those events in the face of Biden's halting performance.

For its part, the Biden campaign is trying to project confidence.

Rob Flaherty, Biden's deputy campaign manager, claimed just after the debate that Biden's campaign had had its "best grassroots fundraising day of the cycle by far" — sending the message roughly 40 minutes after the debate concluded and without sharing additional specifics.

Across the party, the reaction was harsh following Biden's performance Thursday.

"It was a really disappointing debate performance from Joe Biden," said Kate Bedingfield on CNN just moments after the two men left the stage. She served as Biden's own communications director until last year, adding "I don't think there's any other way to slice it."

Julian Castro, a prominent Democrat and former Obama cabinet member and Biden rival in 2020, added online that "Biden had a very low bar going into the debate and failed to clear even that bar."

Another voice Thursday night was former Obama campaign manager David Plouffe who, according to election records, has given to Biden in recent years. He appeared on MSNBC Thursday night and said of Biden's performance "it's kind of a Defcon 1 moment."

The reaction from the larger financial community was also withering.

Ian Bremmer, the president of the Eurasia Group, posted Friday it was inconceivable for a neutral observer to "believe Biden can serve capably as president for another four years." Others are openly predicting Biden will step aside in the days ahead.

Biden himself, in a late night stop after the debate, tried to push back on these concerns telling reporters that he simply had a cold and that "I think we did well."

"It's hard to debate a liar," he added of former President Trump.

The adviser to Hoffman acknowledged the political realities in his note Thursday night.

“Joe is the nominee unless he chooses to step aside," this adviser said in the note, but also noted that “we could imagine better candidates for both parties."

"But we don’t have them.”

Ben Werschkul is Washington correspondent for Yahoo Finance.

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