BUFFALO, N.Y. (WIVB) — India Walton’s apparent victory over incumbent mayor Byron Brown in this week’s Buffalo mayoral primary has been celebrated in progressive circles around the country – and the godfather of the movement has taken notice.

Vermont Sen. Bernie Sanders—who has 15.2 million followers— tweeted Friday that he called Walton to congratulate her on her victory:

Walton proudly considers herself a democratic socialist and is on track to become the first socialist mayor of a major American city since 1960. She will be the only candidate on the ballot in November, though a potential Brown write-in campaign is not off the table.