Devine suggested that any attempt by Sanders to torch Clinton would only incinerate the senator’s own chances. And he added that Sanders himself was all-in on the strategy of abstaining from personal attacks.

“You will never see us run attack ads against her,” he said. “You will never see, from him, the kind of personal, political attack that is common in presidential campaigns. He is not wired that way. He doesn’t believe in it. He thinks people are sick of it.”

Such an approach is not only rooted in personal conviction, as both Devine and unaligned Democratic strategists acknowledge. The thinking is strategic too: Vigorous personal attacks on Clinton would come to seem like politics-as-usual, and would only taint Sanders’ core identity as an idealistic outsider.

“It would come off as awfully inauthentic, and even though I’m sure there are some within his base who would like to see him sharpen his lines of attack, I don’t think the majority would,” said Jim Manley, a former aide to Senate Minority Leader Harry Reid (D-Nev.).