Five candidates for mayor have now asked for public dollars to help keep their campaigns flush with cash, with Michela Alioto-Pier, who opposed public financing in the past, and millionaire venture capitalist Joanna Rees expected to have their applications approved within a week.

They follow City Attorney Dennis Herrera, former Supervisor Bevan Dufty and state Sen. Leland Yee, who have been approved for a combined $1.2 million in public dollars for their campaigns.

Board of Supervisors President David Chiu, former Supervisor Tony Hall and Assessor-Recorder Phil Ting are expected to file in the coming weeks, their campaigns confirmed. Supervisor John Avalos, an advocate for public financing and the most recent candidate to enter the race, is also likely to file.

The Ethics Commission, which oversees The City’s public-financing program, expects candidates to gobble up $4.7 million from the general fund by the end of June, with another $3.6 million available in the next fiscal year.

In order to qualify for the public funds, candidates must raise a minimum of $25,000 with donations from at least 250 city residents. Each candidate can get up to $900,000 in public matching funds depending on the amount of contributions they receive from San Francisco residents, according the Ethics Commission.

Candidates who accept the public funds must agree to a $1.47 million campaign-spending cap.

Alioto-Pier stood against public financing at least once as a supervisor. Along with Supervisor Sean Elsbernd, Alioto-Pier voted against an ordinance extending public financing to mayoral candidates in 2005.

A spokesman for Alioto-Pier said she would wait to comment once the Ethics Commission certifies the donations.

Rees said in a statement she was accepting public money because she wants to participate in a system that “limits the influence of outside money and interests on candidates.”

bbegin@sfexaminer.com