Entering a race that could see him competing against men 15 and 30 years his senior, the 41-year-old Democrat pointedly used YouTube and the social networking sites Twitter and Facebook to disclose that he would seek his party's nomination to succeed Gov. Arnold Schwarzenegger.
The move mirrors Obama's early efforts as a candidate to identify and mobilize supporters through the Internet. But Newsom, who campaigned for Hillary Rodham Clinton in the presidential primary, described it as emblematic of the "intuitive" comfort with technology, transparency and consensus-building he says he shares with Obama.
"There will be legitimate questions nationally -- is change an affectation of the personality of Barack Obama and is it exclusive to Washington, D.C. and the occupant of the White House? Or is that change, that generational mind-set, going to take shape across the rest of the nation, starting with the most populous state?" he told The Associated Press. "We'll see."
In next year's Democratic primary, Newsom could face Attorney General Jerry Brown, who at age 71 is considering seeking the office he held from 1975 to 1983, and Lt. Gov. John Garamendi, 64. Other Democrats mentioned as possible contenders include Los Angeles Mayor Antonio Villaraigosa, 56, and U.S. Sen. Dianne Feinstein, 75.
Newsom, who is a little more than a year into his second term as mayor of California's fourth-largest city, already has a level of name recognition that belies his office and experience. He made international headlines in 2004 when he unilaterally directed city agencies to issue marriage licenses to same-sex couples, a monthlong experiment in civic disobedience ultimately halted by the courts.
While his actions then made him a hometown hero, political observers predicted they could hurt him if he chose to pursue statewide or national office.
Newsom said that to broaden his appeal beyond the San Francisco Bay area, he plans to highlight his background as a successful businessman -- before becoming mayor, he founded a wine store that he parlayed into a string of restaurants -- and as a politician who has been fiscally responsible. For several months, he has been crisscrossing the state and meeting with voters in markedly less liberal areas such as Stockton and San Diego.
The most recent statewide poll, released last month, showed Feinstein leading among the possible Democratic candidates with 38 percent and Newsom running a distant fourth, with 10 percent. Without Feinstein in the race, Brown led with 26 percent and Newsom rose to third-place, with 16 percent.
In deference to Feinstein, Newsom said he would drop out of the governor's race if she entered it soon.
"I think she is still maintaining an interest and she certainly has the right at any time. But I'm not in a position to wait for that decision to be made and I've made that clear to the senator," he said.
Along with his close tie to the same-sex marriage issue, Newsom has another piece of possible political baggage that could be used against him. In January 2007, he was forced to reveal publicly he had an affair with the wife of his mayoral campaign manager and a drinking problem for which he sought treatment.
The disclosures did not impede him from being overwhelmingly re-elected later that year. Last summer, he married actress Jennifer Siebel, who is now four months pregnant with the couple's first child.
"This is the right time in every respect," Newsom said of his candidacy. "I think the experience is there, I think the perspective is there, I think the record is there. The time couldn't be better."
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