Sen. Bernie Sanders (I-Vt.) is weighing into the Philadelphia mayoral race, backing progressive candidate Helen Gym and boosting the national spotlight on the city contest.

Sanders, who has endorsed several down-ballot progressives this year, called Gym a “fighter for working families.”

“She has fought for strong public education, legislation to protect tenants’ rights, and healthcare for all. I am proud to endorse her campaign for mayor of Philadelphia,” he tweeted on Wednesday.

The multi-candidate Democratic mayoral primary, scheduled for May 16, is shaping up to be a battle between progressives and centrists, with Sanders’s support adding Senate weight to her side. 

Just days ago, Rep. Alexandria Ocasio-Cortez (D-N.Y.) backed Gym, following other high-profile lawmakers who tossed their names behind her bid, including Reps. Jamaal Bowman (D-N.Y.) and Ayanna Pressley (D-Mass.).

Gym is competing against several other well-funded candidates who Democrats consider more moderate, and who are in close contention for now. 

The race is gaining more attention after a progressive pulled off a victory in a mayoral primary in Chicago, defying what many expected to be a pull to the center leading up to 2024.