Now, it’s Republicans seeking to use the Sanders surge to portray Democrats as radical and out of touch.

And that’s making many Democrats nervous, said Joe Trippi, who ran Vermonter Howard Dean’s campaign in 2004.

“We can’t lose the presidency. We can’t take a risk by nominating somebody outside the comfort zone. That’s what’s driving the inevitable-ness” of Clinton, said Trippi, speaking about the party establishment’s thinking.

Sanders is unlikely to tone it down for the long-term good of his newly adopted party.

“Bernie is saying what he believes. He’s unlikely to run for president again, and this is his shot … This is as unfiltered and as clear as it comes,” said liberal labor economist Robert Reich, who compared Sanders to past Democratic candidates like Eugene McCarthy and George McGovern.