“It’s disgusting,” says Alison Hartson, a California activist who volunteered for Sanders in 2016. “I am continually shocked by how blatant the establishment Democrats are in their anti-democracy campaign. They are authoritarian, they are totally anti-democratic. And I just can’t stomach it any more.”

On November 2, Hartson became the second Sandernista to announce plans to challenge Dianne Feinstein for the California Senate seat that Feinstein first claimed in 1992. On most subjects, Hartson sounds like the amiable former Orange County school teacher she is. But her piercing rhetoric on the topic of the Democratic establishment promises a lively 2018 primary season. And it foretells a progressive roadblock for any establishment Democrat considering a presidential run in 2020.

“We have decided,” Hartson says, “to take on these establishment puppets.”