QUOTE
what if Biden pushed through the doubts and was nominated at the convention in late August, but was then unable to compete in the November election? Convention rules say, in the event of the “death, resignation or disability” of the nominee, Jaime Harrison, the party chair, “shall confer with the Democratic leadership of the … Congress and the Democratic Governors Association and shall report” to the roughly 450 members of the Democratic National Committee, who would choose a new nominee. They’d also pick a new running mate if they elevated Harris to the top of the ticket.
https://www.politico.com/news/magazine/2024/02/12/joe-biden-democrat-plan-b-nominee-00140790