Can Joe Biden be replaced? If so, by whom?
The fact that leading Democrats are even having to ask the question shows how deep a mess that they - and anyone horrified at the prospect of a second coming for Donald Trump - are now in after Thursday’s night’s disturbing debate.
Trump got away with a 90-minute stream of falsehoods, bluster and exaggeration because the only thing most Americans will remember is the sight of the oldest president yet ageing even more on stage - visibly and painfully.
Not since the very first TV debate in 1960 will have viewer impressions counted for so much. John F. Kennedy famously beat Richard Nixon in the debate by looking and sounding younger and fresher. He then won the election.
Mr Biden was many times worse than Mr Nixon. When even the vice president admits that her boss started off “slow”, you know there’s a problem.
But the bigger problem for Democrats is that Kamala Harris herself is going nowhere fast in the polls, ruling out the one obvious heir in case of a debilitating problem with the nominee.
Trump, for all that he’s a convicted felon, would trounce her in November as things stand.
Who else? California Governor Gavin Newsom is often mentioned. But he said after the debate that the notion that he could replace Mr Biden is “farcical”.
Three other governors could also be in the frame - Gretchen Whitmer (Michigan), Josh Shapiro (Pennsylvania) and J. B. Pritzker (Illinois). None come close to Trump’s standing and national name recognition.
But first there has to be a vacancy. Unless Mr Biden agrees to step aside, his name will go forward when the Democrats convene in Barack Obama’s hometown of Chicago in mid-August.
Any worried Democrats would then face the unenviable task of contesting his nomination, triggering a divisive battle played out live on TV.
In fact the real deadline is even sooner. The rules in Ohio, a battleground state, require the candidates to be confirmed by August 7.
That’s fine for the Republicans: their convention takes place next month.
But the Democrats have very little time to dig themselves out of a Biden-shaped hole.
