Reuben Kantor, who signed on as the manager of Bill Walczak’s mayoral campaign, is stepping down, he said Wednesday night. Kantor, who has worked on campaigns for Gov. Deval Patrick and City Councillor At-Large Ayanna Pressley, cited a hefty schedule that took its toll when he took the job in April.

Kantor said spending a year at the Harvard Kennedy School and juggling final exams and running a campaign took a “tremendous toll.” He added that Walczak, the co-founder of the Codman Square Health Center and a Savin Hill resident, still has his vote in the coming election, “and my admiration.”

Don Walsh, who has served on the board of the Dorchester Bay Economic Development Corporation, is stepping in as the campaign manager.