SAN FRANCISCO -- After publicly apologizing for having an affair with a staff member who's married to his campaign manager, the city's mayor went about business -- though not exactly as usual -- Friday as he vowed not to let his "personal failures" affect his official duties.

Mayor Gavin Newsom kept to a schedule of official events that included campaign events and a Black History Month celebration where he received warm applause, praised other elected officials and listed his administration's accomplishments.

Newsom, 39, responded gratefully to the audience's welcome, his trademark toothy smile standing in stark contrast to the ashen face he wore a day earlier at a hastily called news conference where he acknowledged the soap opera playing out at City Hall.

"I'm sure you are all cognizant of the challenges I committed and continue to reconcile with renewed vigor," said Newsom, 39, stumbling over his words in his only reference to the sex scandal.

The divorced mayor's former deputy chief of staff, Alex Tourk, 39, resigned as manager of the mayor's re-election campaign Wednesday after confronting Newsom about his affair with Tourk's wife, Ruby Rippey-Tourk, 34, who worked for the mayor overseeing commission appointments.

The brief relationship first reported by the San Francisco Chronicle took place a year-and-a-half ago while the mayor was going through a divorce from his wife, Fox News Channel host Kimberly Guilfoyle. Tourk was one of Newsom's top aides since working on his first mayoral campaign, while his wife went to work for the mayor in 2004.

In a statement posted on his campaign Web site, Newsom called the couple, who have a 2-year-old child, "long-time friends" and said, "I humbly ask all of those I have hurt for their forgiveness."

Although the affair was long over and Rippey-Tourk left her job in the mayor's office last spring, it came out this week when she confessed to her husband while undergoing treatment for substance abuse, according to the newspaper.

Tourk earned $15,000 a month as campaign manager. The mayor, who is seeking a second four-year term in November has agreed to keep paying him "the most generous separation agreement possible under election finance rules" until Tourk finds another job, said Eric Jaye, Newsom's senior campaign strategist.

"The guy is so good he will get some great job right away," Jaye said. "He also has a kid and a mortgage and we are totally cognizant of that."

Tourk's deputy campaign manager also resigned, but most of the campaign staff appears to be disappointed by, but sticking with the mayor, according to Jaye.

Speaking to reporters in Washington, D.C. on Friday, California Democratic Party Chairman Art Torres said the revelation about Newsom's affair shouldn't hurt the young mayor's re-election chances, or longer-term political goals. What matters is his performance in office, Torres said.

"Voters are very forgiving. If you are adamant about apologizing and acknowledging that you made errors in judgment, people are very forgiving," Torres said. "But they're not going to be forgiving if you don't perform in office."

Around San Francisco, water cooler chatter Friday suggested many people were willing to let the mayor move on and keep earning his shot at another term. But in an editorial headlined, "What was he thinking," the Chronicle indicated the transgression would be fair game in the months ahead.

The aggravating factors -- betrayal of a friend, violation of one of the most fundamental rules of the workplace -- assure that the sordid episode will damage Newsom's stature even in a city with famously tolerant attitudes about sex," the paper said.