Nate Silver says 'underrated' probability Biden isn't nominee, crazy to think he could serve term

Polling expert Nate Silver argued Monday that President Biden's debate performance has put him at serious risk of not being the Democratic Party's nominee in November and called it one of the "craziest asks" in political history for him to seek a second term.

"I think the probability that Biden isn't the nominee on Nov. 5 is closer to underrated than overrated," Silver wrote Monday in a thread on X.

Silver added that Democrats face many risks maintaining Biden as the head of the party ticket. Biden, already the oldest president in American history, would be 86 by the end of a second term if re-elected. Ronald Reagan, who held the record before him, was 77 when he left office in 1989.

"It's fundamentally a terrible idea to ask the public to make the guy they saw on Thursday president until he's 86," Silver wrote, explaining that Biden leaving "[p]robably won't involve him giving up the office rationally or easily." 

Silver wrote that "[p]ost-debate polls," while bad now, may become even worse. 

He warned that further "senior moments" from Biden are "probably unsurvivable" and that the weaker his campaign becomes, the more likely it is people will abandon the campaign. 

The campaign is already weathering difficult calls and questions from donors, as well as a swelling list of liberal media figures urging Biden to drop out of the race for fear of losing to former President Trump. Silver said it was "fundamentally untenable" to nominate Biden for another four-year term.