California Lt. Governor Gavin Newsom waits to go onstage to speak at the 2014 California Democrats State Convention at the Los Angeles Convention Center on March 8, 2014.
David McNew/Reuters

Gavin Newsom won’t run for Barbara Boxer’s Senate seat

One of the biggest players in California Democratic politics has taken himself out of the running for the state’s first open Senate seat in more than two decades, but he leaves behind what is shaping up to be a crowded field of potential candidates.

California Lt. Gov. Gavin Newsom announced Tuesday that he will not run for the seat to be vacated in 2016 by Sen. Barbara Boxer in order to stay in the Golden State, possibly for a gubernatorial run in 2018.

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“While I am humbled by the widespread encouragement of so many and hold in the highest esteem those who serve us in federal office, I know that my head and my heart, my young family’s future, and our unfinished work all remain firmly in the State of California — not Washington D.C,” Newsom wrote on Facebook. “Therefore I will not seek election to the U.S. Senate in 2016.”

Newsom was seen as one of the strongest potential candidates for the Senate seat, along with state Attorney General Kamala Harris, who has not yet announced her 2016 plans.

But the former San Francisco mayor has long had his eye on the governor’s mansion, and he ran unsuccessfully for the job in 2010. Many observers expected him to skip a Senate bid in favor of the state executive job two years later.

“In the months to come, I look forward to doing whatever I can to help elect California’s next great Democratic Senator — one worthy of succeeding Barbara Boxer and serving this remarkable state of dreamers and doers in the United States Senate,” Newsom added.

Newsom’s move clears a major obstacle for Harris, who has a similar geographic power base, donor network, and group of advisers as Newsom, should she decide to run. But if she does, she will likely not be alone.

This weekend, former Los Angeles Mayor Antonio Villaraigosa, who was also seen to favor a gubernatorial run, announced that he has decided to “seriously consider looking at running for California’s open Senate seat.”

“I was honored to serve as Speaker of the CA Assembly and as Mayor of Los Angeles and it would be an honor to serve Californians again in the future,” he said in statement.

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Meanwhile, politically active billionaire Tom Steyer is reportedly seriously looking at a run himself, and he could be formidable thanks to his ability to fund his own campaign in a notoriously expensive state.

And there a host of other members of congress and statewide elected officials who could get in.

The state heavily favors Democrats, and its new “jungle primary” electoral system means two Democrats will likely face off against each other in a general election.