US President Joe Biden’s re-election bid: First Lady Jill Biden reacts to presidential race challenges

US First Lady Jill Biden on Monday declared herself "all in" on President Joe Biden's bid to remain as the presumptive Democratic presidential nominee, despite calls by some Democrats for him to drop out after his debate performance against Donald Trump shook their confidence in him.

The president himself has brushed aside those calls and insisted anew on Monday that he isn't leaving the race.

"For all the talk out there about this race, Joe has made it clear that he's all in," the first lady told a military crowd in Wilmington, North Carolina, the first of three battleground states she was visiting.

"That's the decision that he's made, and just as he has always supported my career, I am all in too," said Jill Biden, who teaches English and writing as a community college professor.

Her daylong tour was part of the Biden campaign's broader effort to rebound from the president's halting performance against Trump in last month's debate.

The debate led some congressional Democrats and others to call on him to let another candidate challenge Trump because they no longer believe the 81-year-old president is mentally and physically capable of defeating the former Republican president in November.