Crypto bettors on decentralized blockchain betting site Polymarket have driven up the odds of him dropping out of the race for re-election following revelations President Joe Biden tested positive for COVID-19 on Wednesday.

Bettors now see a 66% chance of him bowing out, nearing the odds reflected one week ago when several allies signaled it was time for him to step aside.

More than $16.4 million is riding on the wager, one of the largest on the prediction market platform that promises “live, unbiased 2024 election forecasts.”

According to the Associated Press, Biden tested positive for COVID while traveling in Las Vegas, where he was set to speak at the National Convention for UnidosUS, a Hispanic civil rights and advocacy organization.

The White House said he would recover at his home in Delaware and “continue to carry out all of his duties fully during that time.”

The revelation came mere hours after Biden said in an interview that he would consider dropping out if faced with a “medical condition.”

The New York Times reported Wednesday that he told Ed Gordon of BET News he'd follow his doctor's advice.

Biden's dropout odds on Polymarket had slipped below 50% on Friday.

The Covid diagnosis has also pushed Biden's odds of being the outright winner of the U.S. presidential election in November down to 13% on Wednesday, allowing Vice President Kamala Harris—who has frequently flipped her boss in the wager—to return to second place.

More than $268 million is riding on that question, where former president Donald Trump has held the top spot for weeks. He's now favored to win by crypto bettors at 69%.

Punters still expect Biden to be the ultimate Democratic party nominee. Over $125 million is riding on that bet, where Biden is still the top prospect with a 49% chance, Polymarket data shows.

Edited by Sebastian Sinclair