According to CoinDesk, the probability of President Biden withdrawing from the presidential race has reached a record high of 55% on Polymarket. This surge in odds comes after former President Barack Obama privately expressed concerns about Biden's campaign and debate performance. The Washington Post reported that Obama, worried about Biden's reelection chances following a lackluster debate performance, has been privately advising and supporting him. Despite this, Obama continues to publicly express confidence in Biden's campaign.

Bettors are uncertain about the timing of Biden's potential withdrawal. The market predicts a 42% chance that Biden will withdraw before the Democratic convention, scheduled for August 19. The Democratic party has reportedly prepared for the possibility of Biden's withdrawal, according to the New York Times. The process of securing a new nominee, however, would be complex.

The most straightforward option would be to nominate Vice President Kamala Harris, Biden's running mate. The market, anticipating this as the path of least resistance, increased Harris' odds of becoming the Democratic nominee to 31% on Tuesday. Polymarket bettors assign a 13% chance of Harris winning the presidential election and a 16% chance to Biden.

The general presidential election contract on Polymarket has seen more than $211 million in bets, with nearly $10 million wagered on the possibility of Biden dropping out.