This article is from the archive of our partner National Journal

Tom Steyer has officially taken himself out of the 2016 California Senate race. But he may have his eyes on something else.

In a Huffington Post op-ed Thursday afternoon, the billionaire climate activist said that while he had given serious thought to a run for retiring Sen. Barbara Boxer's seat, he had chosen not to join the race.

But a source close to Steyer said the 57-year-old still has designs on running for office, saying "it's no longer a question of 'if.'" Steyer has been mentioned as a potential candidate for governor in 2018 when incumbent Jerry Brown's final term ends.

The source close to Steyer said a future campaign would "need to be the right office and be an office where he believes he can do more and accomplish more in the inside than he can from the outside."

That means, the source said, an office where executive decisions are made, or "substantive progress" can happen because of potential future Democratic control in Washington, where right now Republicans hold Congress. That could bring the Senate back into Steyer's sights in 2018, when Sen. Dianne Feinstein's current term is up, if she does not seek reelection.

In the op-ed Thursday, headlined "The Fight For Justice Starts With Climate," Steyer echoed themes President Obama outlined in his Tuesday State of the Union address on economic inequality and the American dream.

"To move forward," he wrote, "we need leadership in government and outside of government that is committed to environmental justice, economic justice, and education justice."

Steyer's absence in the Senate race helps ensure he can focus more heavily on using his fortune to help other candidates in the 2016 cycle, something the Bay Area resident hinted at Thursday while standing down from his own run.

"Given the imperative of electing a Democratic president—along with my passion for our state—I believe my work right now should not be in our nation's capital but here at home in California, and in states around the country where we can make a difference," Steyer said in his post.

Steyer spent $74 million in last year's elections trying to elect candidates to the Senate and governor's mansions that support action on climate change. He had mixed results, coming up short in four of the contests.

His announcement comes after he toyed with launching a Senate bid in another Huffington Post op-ed last week. In that post, he asserted that "Washington needs to be shaken up."

Last week, California Attorney General Kamala Harris announced her candidacy for the seat. Momentum for her grew quickly: The Democratic Senatorial Campaign Committee lined up behind her just minutes after the announcement, and a day later, powerhouse fundraiser and progressive hero Sen. Elizabeth Warren of Massachusetts endorsed her, calling for supporters to raise $25,000 in Harris' election effort.

Despite Steyer's extreme wealth, he likely would have had trouble running against the much-better known Harris.

The flurry of California Senate activity comes just weeks after Boxer, who has served in the chamber for 21 years, announced that she would retire at the end of her term.

This article is from the archive of our partner National Journal.

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