McCormack was the first woman to go public with harassment allegations against Filner, who took office last December. She claimed the mayor asked her to work without panties, demanded kisses, told her he wanted to see her naked and dragged her in a headlock while whispering in her ear.
Other accusers contend that he cornered, groped and forcibly kissed them.
Should Filner resign, City Council President Todd Gloria would become acting mayor until a special election is held.
Associated Press writer Elliot Spagat contributed to this report. Blood reported from Los Angeles.
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