A Biden donor says giving him cash is a waste of time and money if that bad debate showed what Biden's really like

"If it's as bad as what we all witnessed on Thursday night, then he needs to put his country first and step aside immediately," investor Whitney Tilson said of President Joe Biden on Saturday. Andrew Caballero-Reynolds/AFP via Getty Images

• Investor Whitney Tilson says he felt "deceived" after watching the Biden debate with Trump last week.
• Tilson said Biden should pull out "if the man I saw at the debate is the real Joe Biden right now."
• The Biden donor said it would be a "waste of my time and money" to continue backing him.

Investor Whitney Tilson, a longtime donor to President Joe Biden, says he's reconsidering his support for Biden after his stumbling performance at last week's presidential debate.

"I feel deceived. For months my Republican friends have been sending me videos from Twitter and Fox 'News' that appear to show Biden's dementia," Tilson wrote in an X post on Saturday.

"Though I was concerned, I was mostly able to dismiss these often deceptively-edited videos as the usual Republican attack machine idiocy because I remember how they tried to do the same to Hillary in 2016," he continued. "But the debate changed all that."

The former hedge fund manager said Biden must withdraw from the presidential race if his bad performance on Thursday's debate was not a one-off.

Biden's withdrawal, the longtime Democratic donor said, is now critical if the Democrats want to have any chance of beating former President Donald Trump in November.

"If it's as bad as what we all witnessed on Thursday night, then he needs to put his country first and step aside immediately," Tilson wrote.

"I will fight to my dying breath to stop Trump and his toxic Trumpism, but if the man I saw at the debate is the real Joe Biden right now, then it would be a waste of my time and money to support him because he has almost no chance of beating Trump," he continued.

Tilson added that he would still vote for Biden if he stays on but would instead "channel all of my energies into helping Democrats hold the Senate and retake the House."

Representatives for Biden and Tilson did not immediately respond to requests for comment from BI sent outside regular business hours.

Remarks made by high-profile donors like Tilson are likely a source of concern for the Biden campaign, which has been working hard to assuage supporters of Biden's mental acuity following last week's debate.

Biden's performance on Thursday was riddled with gaffes and stumbles as he sought to make the case for his candidacy against his GOP rival, Trump.

The setback on the debate stage has only compounded fears and worries about Biden's cognitive decline and his fitness for the Oval Office. Some have even called for the 81-year-old to be replaced as the presumptive Democratic nominee.

Billionaire Mark Cuban, who once said that he'd still vote for Biden even if the president "was being given last rites," said on Friday that he was willing to consider swapping Biden out for another candidate.

"Trump is far better than Biden at soundbites and marketing. That's reality," Cuban said in an X post. "For that reason, I'm also open to the discussion to replace Biden and/or Harris.

"It's not like Trump's approval ratings are high. They aren't. It could be an open door to find someone immediately out-performing Trump," he continued. "But if that doesn't happen, I'm still voting for Biden.

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