Washington (CNN) On Tuesday morning, Jeff Weaver, who managed Bernie Sanders' 2016 presidential campaign, said this to C-SPAN's John McArdle about the possibility of a rerun by the Vermont socialist in 2020:

"He is considering another run for the presidency and when the time comes I think we'll have an answer for that. But right now he's still considering it."

That's both a) not terribly surprising and b) extremely important.

Not surprising in that Sanders has never really stopped running a national campaign since his primary loss to Hillary Clinton in 2016. Extremely important in that Sanders is -- and is likely to remain -- the prime mover in the Democratic presidential field.

That's not to say Sanders is the current frontrunner for the nomination. He's not. Former Vice President Joe Biden is -- as CNN's Harry Enten argues convincingly here.

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