Facing a crush of TV cameras Thursday, Gavin Newsom made the toughest admission of his public life: He confessed to an affair with his former appointments secretary, the wife of his good friend and campaign manager.

“I want to make it clear that everything you’ve heard and read is true,” the usually boisterous San Francisco mayor said in a hushed tone, “and I am deeply sorry about that.”

His contrition marked a low point in a stellar rise that had made Newsom, at 39, one of the most popular and talked-about mayors in the country.

He is again today, but not for reasons he had hoped.

The City Hall sex scandal that burst wide open Thursday had friends and political allies asking: Just what was he thinking?

Newsom had built an international reputation as a bold thinker – promoting gay mar

“What is going on inside his head?” said David Binder, a San Francisco political insider who knows Newsom casually and has worked for his political allies. “You guess this is probably something very difficult for him to admit and he has some issues he has to resolve.”

Details of the months-long 2005 affair, widely rumored at City Hall for some time, have not been confirmed by Newsom’s team. And neither the campaign manager nor his wife returned several phone calls from the Mercury News.

Alex Tourk, 35, has said only that he is resigning as manager of Newsom’s re-election campaign for personal reasons.

But friends and City Hall insiders say Newsom, at the time in the middle of his divorce from Kimberly Guilfoyle, and Ruby Rippey-Tourk, 34, had the affair while she worked as his appointments secretary.

Six months ago, Rippey-Tourk took a new job as a TV and radio host for Benefit, a San Francisco media company that highlights non-profit works and philanthropists. The Benefit Web site description of her show says “Ruby Tourk interviews the people, the foundations and the volunteers in the community who are leading the charge, like Mayor Gavin Newsom, Sharon Stone, Robin Williams.”

Rippey-Tourk, who at one time was a TV anchor in Santa Rosa, took a leave of absence from the mayor’s office last summer and sought treatment for substance abuse in Arizona. She admitted the affair to her husband last week.

Tourk, who had worked for Newsom as a key deputy chief of staff before heading his re-election campaign, held a one-hour closed-door meeting Wednesday with Newsom at his campaign office, where he told Newsom he knew about the affair. Then he quit.

Newsom, in apologizing to his former aide by name at Thursday’s news conference, called his behavior a personal lapse of judgment.

“I have hurt someone I care deeply about, Alex Tourk, his friends and family, and that is something that I have to live with,” the mayor said.

Staying on

But Newsom, who also apologized to his own family and members of his administration, said he intends to carry on as mayor.

The response to the scandal from fellow politicians and city residents ranged from sadness to outrage.

“I can tell you there is no more loyal member of the Newsom administration than Alex Tourk,” said Supervisor Chris Daly, who often is at odds with Newsom’s policies. “I would think everyone who has a relationship to Gavin Newsom is probably second-guessing what the content of his character is. That hurts.”

Newsom was the city’s youngest mayor in a century when he took office in 2004. In a short time, he’s built an international reputation as a big thinker. But closer to home he’s made some big fumbles, including initially ignoring the 49ers threat to move to Santa Clara, the subsequent pulling out of an Olympics bid, and a messy love life that makes even progressive San Franciscans cringe.

“Everyone is allowed to stumble,” said Supervisor Tom Ammiano, a onetime mayoral rival. “I don’t think he has too many more stumbles in his quota.”

It’s an election year in San Francisco, but, so far, no major competition has emerged to take the mayor on for a second term. He has enjoyed unusually high approval ratings during his three years in office.

But his personal life has been beset with turmoil, starting with a long separation from Guilfoyle, a cable TV legal commentator who has since remarried, had a child and lives in New York City. Newsom’s divorce became final a year ago.

Over the past year, Newsom has been linked to a series of girlfriends, including television actress and Scientology supporter Sofia Milos and a 20-year-old restaurant hostess and model. Newsom has expressed frustration with the media’s fascination with his love life.

He also has publicly wrung his hands about his failure to have a meaningful personal life and once complained how he goes to bars and restaurants almost nightly, and often alone, where he bones up on policy homework.

Newsom reportedly has a new girlfriend whom he took to Switzerland last week to attend the World Economic Forum in Davos.

Turnabout

It’s a far cry from the early days of his tenure when he and then-wife Kimberly lighted up the pages of Harper’s Bazaar and set tongues wagging coast-to-coast after the couple appeared in sexually charged magazine photos of the duo on the floor of the Gordon and Ann Getty mansion. The magazine heralded them as the “New Kennedys.”

Friends say the Guilfoyle divorce was a personal blow, but others close to him say he is just showing the frustrations many other politicians feel, but aren’t brave enough to admit.

“He needs to lead a more ascetic lifestyle,” said Chris Lehane, a San Francisco political consultant who worked in the Clinton White House during the Monica Lewinsky scandal.

“Getting down on his hands and knees and asking for forgiveness was a good start,” Lehane added. “People will watch how he handles this and that will determine his political future.”

In San Jose, former Mayor Ron Gonzales, who in 2000 left his wife for a young mayoral staffer whom he eventually married, never recovered popular support. But there are a litany of politicians, from Clinton and Rudy Guiliani to Ted Kennedy and Arnold Schwarzenegger, who have survived politically after the revelation of sexual escapades.

There is no San Francisco city law forbidding one city employee from having a sexual relationship with another, even if it involves a superior and subordinate. However, if Rippey-Tourk says she felt intimidated to carry on a relationship because the mayor was her boss, she could file a sex harassment claim, the city attorney’s office said.

“This behavior was inappropriate, but it’s not going to keep him from getting on with the business of the city,” said Eric Jaye, Newsom’s longtime political adviser. “He told the Tourks he was deeply sorry for a profound lapse of judgment and he would do anything in his power to atone for that by being a better mayor.”

Still, some observers think Newsom crossed the line.

“Having an affair with your campaign manager and good friend’s wife is unacceptable in the public’s eyes,” said Barbara O’Connor, who teaches politics and the media at California State University-Sacramento. “Being handsome and charming doesn’t mediate the sense of outrage. You have to have some standard.”

And in an ironic twist, an ultra-dapper Gavin Newsom appeared on the cover of Benefit Magazine last fall, with the title “Why Gavin Gives.”

In the story, Alex Tourk is quoted as saying he has great respect for Newsom.

“It’s one thing to talk about the world the way it should be. It’s quite another to roll up your sleeves. … Anyone who questions his sincerity simply doesn’t know him.”

On Thursday, that same sincere mayor apologized to the world for sleeping with the man’s wife.