Hello and welcome to News Hour from the BBC World Service.

We're coming to you live from London. My name's Paul Henley.

Last night's televised US election debate, the first of the campaign

between Joe Biden and Donald Trump, was always likely to be pivotal, but such was

the performance of the 81-year-old incumbent president that the overwhelming reaction the and many Democrats are the ones asking it.

The 90-minute exchange was bad-tempered, personal,

and marked by Mr Trump making a stream of easily debunked claims,

but it was on Mr Biden's faltering presentation and his inability to bring vigor and

stamina to the debate that most attention fell.

Well, concern among Democrats was clear straight after the debate speaking to

MS NBC the former Democratic senator Claire McCaskill who was meant to be

cheerleading for the president said many in the party felt it was a moment of

crisis.

Joe Biden had one thing he had to do tonight and he didn't do it.

And that was reassure America that he was up to the job at his age.

My phone blowing up with senators and campaign operatives,

big donors from all over the country.

There is more than hand-winging tonight.

I do think people feel like that we are confronting a crisis.

So in the wake of this debate, can the Democrats really afford to stick with the status quo?

And if there were to be a change of candidate what would need to happen.

Dr Thomas Gift is Associate Professor of Political Science and Director of the Center on

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