San Francisco Mayor Gavin Newsom, who propelled the debate over gay marriage but struggled to find a popular message outside the San Francisco Bay area, dropped his bid for California governor on Friday.

A statement issued by his campaign said he was unable to devote the time needed to run an effective campaign, citing "a young family and responsibilities at City Hall."

"This is not an easy decision," he said. "But it is one made with the best intentions for my wife, my daughter, the residents of the city and county of San Francisco, and California Democrats."

His announcement was not a surprise to those following the Democratic campaign. Newsom, 41, was unable to find the same popularity throughout California that he enjoys in his home city.

Attorney General Jerry Brown had a 7-to-1 fundraising edge over Newsom, even though Brown has not officially announced his candidacy. A Field Poll earlier this month showed Newsom trailing Brown by 20 points among likely Democratic voters.

Newsom failed to gain traction even after holding months of town hall meetings throughout the state and ringing up an endorsement from former President Bill Clinton.

A Clinton fundraiser that had tickets selling at up $50,000 a piece failed to give Newsom the financial boost he needed to compete with a likely run by Brown.

Newsom's exit from the race leaves Brown as the only well-known Democrat seeking the party's nomination. Brown did not immediately return a call seeking comment.