The vice-president would be a logical choice if Biden does opt out, but some are already looking to other contenders

Joe Biden’s stumbling debate performance left Democrats so panicked some are searching for an alternative to replace the 81-year-old president as the party’s standard-bearer.

Biden has given no indication that he intends to exit the race, and his campaign has flatly dismissed the suggestion. But that has done little to silence critics who are openly questioning whether Biden is the right person to take on Donald Trump, a figure the president – and his party – view as a grave threat to American democracy.

The 90-minute debate is scheduled for 9pm ET inside a CNN studio in Atlanta, with Jake Tapper and Dana Bash as moderators

• Biden-Trump presidential debate – live updates

Joe Biden and Donald Trump will hold the first of two scheduled US presidential debates on Thursday, a high-stakes rematch between two well-defined political foes.

The earlier-than-usual confrontation will give both men a chance to make their case for a second-term to what could be one of the largest television – and internet – audiences of the election cycle.

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