Odds of United States President Joe Biden being reelected fell as low as 9% on decentralized predictions platform Polymarket as punters speculated whether Vice President Kamala Harris will replace Biden as the Democrat candidate.

Biden’s odds have since briefly recovered slightly, now at 10% in Polymarket’s $226 million “Presidential Election Winner 2024” market.

Former President and Republican candidate Donald Trump is the favorite with 61% odds, and Harris is in second place with 19% odds.

Share prices reflecting Biden’s odds on predictions platform PredictIt have similarly dropped from $0.25 to $0.20. Harris is now the leading Democrat candidate — however, Trump still holds the highest valued “Yes” shares at $0.58.

It comes amid increasing concerns from media and outside commentators suggesting that he may not be fit for a second term.

According to CNN, the President reportedly worried several U.S. governors in a White House meeting on July 3 where he jokingly said: "I’m fine — I don’t know about my brain, though.”

The same report claims Biden said he will stop scheduling events after 8 pm now in order to get more sleep.

Biden didn’t do himself many favors the next day when he mistakenly described himself as the “first black woman” to serve as U.S. President in a radio interview — a clip which has been circulating on social media since. 

Polymarket now shows a 66% chance that Biden will drop out before the Nov. 4 U.S. election, with Harris being the most likely Democrat candidate to face off with Trump.

Related: Are politicians using crypto to influence the US elections?

However, Biden has stressed he has no intention to step down despite increasing pressure to do so.

“I’m not going anywhere,” Biden reportedly said during an Independence Day speech at the White House on July 4.

Neither Biden nor Trump mentioned Bitcoin (BTC) or digital asset-related matters during the first Presidential Debate on June 27.

Trump and Biden are scheduled to face off with each other again in the final Presidential Debate on Sept. 10.

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