By David Siders

Lt. Gov. Gavin Newsom said Wednesday that he is opening a campaign account for governor in 2018, allowing him to raise money for a wide-open -- and far-off -- contest to succeed Jerry Brown.

Newsom, a former mayor of San Francisco, has long held gubernatorial ambitions, and his candidacy was widely expected. When he announced in January that he would not run for U.S. Senate in 2016, it was with an apparent eye to the governor's office in 2018.

"I've never been a fan of pretense or procrastination," Newsom said in a statement posted on Facebook and e-mailed to supporters. "After all, our state is defined by its independent, outspoken spirit. When Californians see something we truly believe in, we say so and act accordingly -- without evasiveness or equivocation."

Newsom, a 47-year-old Democrat, said in an interview that he had told Brown of his decision and that the governor was "very gracious." He declined to characterize the conversation except to say that "Jerry Brown's a good person to ask advice" and that they did not discuss endorsements.

Newsom breezed to re-election last year and has about $3 million left from that campaign. His announcement could put added pressure on Antonio Villaraigosa, the former mayor of Los Angeles, to decide if he will run for U.S. Senate in 2016. Villaraigosa will likely announce a decision soon. He is expected to run for governor if he does not run for Senate.

Other potential Democratic candidates for governor include Tom Steyer, the billionaire environmentalist and -- if she loses her campaign for Senate -- Attorney General Kamala Harris.

Ashley Swearengin, the Fresno mayor and failed state controller candidate, and Kevin Faulconer, the mayor of San Diego, are considered potential future candidates for statewide office on the Republican side. Newsom briefly competed with Brown for the Democratic nomination for governor in 2010 but dropped out more than a year before the election.

Despite their long-standing connections, the two politicians had a distant relationship when Brown and Newsom first got to Sacramento in 2011. Newsom said Wednesday that their relationship has "substantially improved."

Newsom, who has few official duties as lieutenant governor, said he will spend time in coming years developing policy proposals for his campaign. He will also be raising money, an effort Newsom said will require "a long runway" of time. Asked how much he will have to raise, Newsom acknowledged the astronomical cost of statewide campaigns in California but said, "I honestly don't know."

Newsom gained political attention while mayor of San Francisco for the universal health care law he signed and for authorizing gay marriages in the city when state law still prohibited them.

On Wednesday, Newsom said in his prepared statement that Californians "are blessed with the remarkable leadership of Gov. Jerry Brown, who in the face of long odds has led our state to firm fiscal footing and brought us to the enviable position of dreaming -- and achieving -- big dreams again."

However, Newsom said "long-term challenges remain daunting," including concerns about climate change, poverty, economic growth, public education and college affordability.

(c)2015 The Sacramento Bee