From our Mayor May I Files, Sacramento’s reputation as a breeding ground for big city mayors in the post-term limits era continues. First, there was Willie Brown, who ran for San Francisco mayor after 15 years as Assembly speaker. One of his successors, Antonio Villaraigosa, followed suit in Los Angeles. Bob Hertzberg ran for the L.A. mayor job, and speculation has swirled that Sen. Alex Padilla may be a candidate for that post in 2013. In the meantime, Sen. Leland Yee declared his candidacy for San Francisco mayor this week, joining a crowded field that includes City Attorney Dennis Herrera and supervisor Bevan Dufty. If Steve Cooley holds on to win the attorney general’s race, look for Kamala Harris to enter the mayoral fray. Remember, when Gavin Newsom vacated the job in January, the Board of Supervisors must appoint a steward to lead the city until an election is held next year. Meanwhile, in San Diego, a bunch of Sacramento names from Chris Kehoe to Denise Ducheny have been mentioned as potential candidates. And Republican Assemblyman Nathan Fletcher appears to be inching closer to announcing his candidacy for the job.