Can Bernie Sanders train the next generation of progressive candidates?

Sen. Bernie Sanders of Vermont may not be eyeing higher office again, but he’s still drawing thousands of supporters and raising serious money, making him one of the Democratic Party’s biggest forces. Now Sanders is using that momentum to boost the next generation of progressive leaders.

According to Politico, Sanders is teaming up with Run for Something and other outside groups to help would-be candidates with the nuts and bolts of campaigning—how to file, hire, raise money, and win. The effort could usher in a wave of young...