Warren is in her 70s and is UNLIKEABLE.
Klobuchar is a trooper and may take the job.
Newsom is the best person to challenge Biden for the nomination, even at this late stage. He would have to give up running the ninth-biggest economy in the world and no way to be Biden's VP candidate.
Whitmer is possible.
Academic though, because the Democrats lacked the imagination and fortitude to give Biden the push.
Best.