BOSTON — Dana Depelteau, a hotel manager, had just gone public with a long-shot candidacy for mayor in Boston when he noticed that someone in city politics was going after him online.
The effect of this attack, he said, was lightning-fast and pervasive. The morning after he announced his candidacy on Twitter, he showed up at his local barbershop and, while staring at himself in the mirror, overheard a customer describing his views as white supremacist.
"I'm thinking, 'Man, politics is dirty,'" recalled Depelteau. He rushed home to fire back at his critic, a sharp-edged progressive who had dug up some of Depelteau's old social media posts and was recirculating them online. But that, he discovered, was a big mistake.
"I didn't know how old she was," he explained. "I just knew she was a prominent person."
That is how he became aware of Calla Walsh, a leader in the group of activists known here as the Markeyverse. Walsh, a 16-year-old high school junior, has many of the attributes of Generation Z: She likes to refer to people (like the president) as "bestie." She occasionally gets called away from political events to babysit her little brother. She is slightly in the doghouse, parent-wise, for getting a C+ in precalculus.
She is also representative of an influential new force in Democratic politics, activists who cut their teeth on the presidential campaigns of Sens. Bernie Sanders and Elizabeth Warren.
The full strength of these activists — many of whom are not old enough to vote — did not become clear until last fall, when they were key to one of the year's most surprising upsets, helping Sen. Edward Markey defeat a primary challenge from Rep. Joe Kennedy III, who had been heavily favored to win.
In conversation, Walsh tends to downplay her movement, describing them as "Markey teens" and "theater kids" who "formerly ran, like, Taylor Swift or K-pop stan accounts."