Chris Dempsey

Transportation for Massachusetts Director Chris Dempsey announced his departure from the advocacy group Tuesday as he continues to pursue his campaign for state auditor.

Dempsey, who had already been fundraising while exploring a bid for the office, told Transportation for Massachusetts members and supporters in an email that he is “stepping down to prepare for and pursue a candidacy for Massachusetts State Auditor in the 2022 election cycle.”

Josh Ostroff, the coalition’s partnerships director, will take over as interim director following Dempsey’s departure after more than four years at the helm.

“We have accomplished much, but there is still much more work to do,” Dempsey wrote. “Our current transportation policies fall short of what our residents and businesses deserve, and the burden falls especially hard on underserved and overburdened communities. It is critical that we continue advocating for change.”

Methuen Sen. Diana DiZoglio is already running for auditor and raising campaign funds. Her colleague, Taunton Sen. Marc Pacheco, has been discussing a possible bid but has not yet decided whether to enter the race.

Dempsey, a Brookline Democrat, has had a busy week. On Monday, he announced via Twitter that he got engaged over the holiday weekend.