A poor debate performance has fuelled Democrat unease about Mr Biden's candidacy.
The first presidential debate is done and the aftermath has not been good for the incumbent, Joe Biden.
Some Democrat politicians and operatives reportedly texted CNN commentators with hopes that Mr Biden, 81, would step aside.
Some floated the possibility of going to the White House and publicly stating concerns about him remaining as candidate.
But if Mr Biden were to drop out, it would be a free-for-all. There is no official mechanism for him or anyone else in the party to choose his successor, meaning Democrats would be left with an open (Democratic National Convention (DNC) in Chicago from August 19-22.
This is the thing with a primary season. If something happens late in the season, then how do you go back and change the results from earlier in the season?
Let's say for instance Biden listens to all the "sky is falling" pundits and retires now. How does the DNC choose its candidate? I'm not very familiar with procedures for a closed system like that. Do they do an open convention and let the delegates vote on whoever they want? Do they have a list of candidates to vote one at the convention? Who makes up that list?
There, a candidate must win support from the majority of "delegates" - party officials who formally choose the nominee. Delegates are assigned to candidates proportionally based on the results of each state's primary election.
This year, Mr Biden won almost 99% of the nearly 4,000 delegates.
According to the DNC rules, those delegates are "pledged" to him, and are bound to support his nomination.
But if Mr Biden were to drop out, it would be a free-for-all. There is no official mechanism for him or anyone else in the party to choose his successor, meaning Democrats would be left with an open convention.
Presumably, Mr Biden would have some sway over his pledged delegates, but they would ultimately be free to do as they please.
That could lead to a frantic contest erupting among Democrats who want a shot at the nomination.
If Biden dies of natural causes before the convention, they will use the convention to elect a new candidate. It’s pretty obvious Gavin Newsom has been positioning himself for such a scenario.