Several things come to mind.
1) As a partisan Dem, expect Joe to make partisan statements.
2) tRump may very well NOT be on the 2020 GOP ticket.
3) There are a number of possible Dems who are almost certain losers.
I think that list includes Warren, Gillibrand, Booker, Bernie, Biden, Klobuchar.
All of the above would do much better to remain right where they are.