With growing concern about the president’s cognitive ability, the Democrats face an excruciatingly difficult dilemma – whether to call for their leader, 81-year-old Joe Biden, to drop out of the race. Guardian US political correspondent Lauren Gambino tells Nour Haydar why the Democrats are torn over who should lead them to the next election and just how critical the coming weeks are for Joe Biden’s campaign You can support the Guardian at theguardian.com/fullstorysupport