Let’s go back in time about six months — back to October when Bernie Sanders’s heart attack prompted the mainstream media to declare his campaign all but dead. Most could barely hide their glee.

Then something remarkable happened in Queens. With Alexandria Ocasio-Cortez warming up a crowd of tens of thousands, a recovered Sen. Sanders took the stage to the sound of Sheer Mag’s “Expect the Bayonet.”

It had the feeling of a comeback tour, and rightly so. Since then, Sanders has brushed aside worries of his being “too old,” climbed to a lead in the polls, and won the popular vote in seven primaries. With the field cleared and the execrable Joe Biden now ahead in the delegate count, Sanders is again the underdog, but not yet defeated. If Sanders’s rallies since then have often taken on an air of a concert, there is good reason for it — and it comes straight from the top. “One of the questions Bernie always asks before an event,” Sanders’s deputy campaign manager told CNN, “is do we have a band.” He’s gained the endorsement and support of Jack White, Las Cafeteras, Cardi B, Killer Mike, M.I.A., Bon Iver, Lizzo, Neil Young, Zola Jesus, Ana Tijoux, Michael Stipe, Vic Mensa, Jeff Mangum, Public Enemy, and a long list past this one. If every meaningful social movement has its soundtrack, then the one around Sanders is uniquely vast and varied.