Democrats have ways to replace Joe Biden at the top of their presidential ticket after a harrowing debate against Republican Donald Trump — but doing so without their standard-bearer’s acquiescence would be a daunting task.

Party members once united behind Biden are now scouring candidate resumes and researching rules for a contingency plan to present voters with a different nominee after a universally panned performance Thursday night cemented worries about the president’s ability to serve a second term.

"The easiest one is, Biden takes himself out of the race,” said Elaine Kamarck, a Democratic National Committee member and author of a book about the presidential nominating process. "Then yes, there’s rules and procedures and the party would replace him.”