It’s not just senators being courteous to a colleague known for being something of a loner in the upper chamber. Instead, Senate Democrats respect the durable political movement he’s built over the past five years that threatened to topple Hillary Clinton and a populist streak that could be wielded against Trump to win over some of his voters.

“I do believe he can beat President Trump,” said Sen. Kirsten Gillibrand (D-N.Y.), who sought the presidential nomination earlier this cycle. “What Bernie has shown us until now is that he has a very broad base of very, very passionate followers. That is the first thing you need for a campaign on any level. Especially in a red or purple district.”

“He’s running even with [Trump] in the national polls and… his win in Nevada shows that he won over all the demographics. So I think he’s looking really strong,” agreed Democratic Sen. Tom Udall of New Mexico, a state that Trump wants to flip in November. “It looks like he’s the leader right now and he’s doing very well.”