Calls for Mr Biden to stand down began immediately after the end of the 90-minute debate in Atlanta, Georgia, which left supporters at an official viewing party with their heads in their hands.
The event went so badly that some speculated that Mr Biden may have been encouraged to hold an unusually early debate to give his party time to find a replacement.
Several liberal media outlets that have generally dismissed concerns about Mr Biden’s age published articles calling for a new nominee, while the president’s favourite news anchor, Joe Scarborough, said: “If he was CEO and he turned in a performance like that, would any Fortune 500 corporation in America keep him as CEO?”
The rules of the Democratic Party make it almost impossible for a challenger to remove Mr Biden at this stage of the election cycle, after he won the party’s primary race virtually unopposed this spring.
But some in his party hope he will stand down voluntarily, and have discussed asking Mr Obama, Hillary Clinton, or his wife Jill to urge him to do so.
It is thought that any attempt at a managed withdrawal from the race would also involve Chris Coons, a longtime Biden ally in the Senate, and Hakeem Jeffries, the minority leader of the House of Representatives.