Newsom said after he learned of the state's decision to lift a ban on same-sex ceremonies this week, he immediately contacted his father, who had opposed his decision to allow such marriages to take place in San Francisco, the Los Angeles Times reported Saturday.

"He said, 'I've really thought about this and you've changed my mind on this gay marriage thing,'" the mayor said of his discussion with his father. "That's what this is all about."

NDN Director Simon Rosenberg told the Times the California ruling will expose Newsom's dedication to his beliefs to the rest of the nation.

"Until now, what voters know about Newsom outside San Francisco is still shallow," said Rosenberg, whose company serves as a political think tank. "But this cause will help him define himself. Now he can speak to a state and national audience on an issue where he has stuck by his principles."

The Times said Newsom first became dedicated to the same-sex marriage cause in 2004 after hearing a conservative speech by President George Bush.