When California Senator Barbara Boxer announced that she would not seek reelection in 2016, analysts and political pundits immediately began to speculate who might seek to claim her seat in the U.S. Senate. According to several sources, it looks like billionaire environmental activist, and former Farallon Capital  founder, Tom Steyer is seriously considering throwing his hat in the ring for the soon-to-be-open seat in the Senate.

Analysts note that while his political activism has helped to raise Steyer’s name recognition, other well-known Democrats are reportedly also considering making a run for Boxer’s seat, including California Lt. Gov. Gavin Newsom, California Attorney General Kamala Harris and former Mayor of LA Antonio Villaraigosa.

California Billionaire Tom Steyer May Run For US Senate in 2016

Tom Steyer definitely interested

A POLITICO source close to Steyer noted he has been approached by some in the liberal activists to run for Boxer’s seat, but others have urged him to run for governor of California in 2018. The source said running for Senator Dianne Feinstein’s seat if she retires in 2018 is also an option under consideration.

The source also said Tom Steyer began reviewing polling data and making calls to California labor and political figures, immediately after Boxer announced that she would not seek reelection in 2016. In addition, Steyer is consulting with contacts he made spearheading advocacy campaigns focusing on ballot measures in California in 2010 and 2012.

Steyer has been politically active for some time

Of note, Tom Steyer has spent tens of millions of dollars on federal elections over the last few years, spending over $65 million in the midterm elections alone, working to make climate change a higher-profile political issue. Any campaign by Steyer would almost certainly be one of the most environmentally focused in history, and a real-world test of his his belief that climate change is a critical issue that voters care about.

Although Steyer is clearly very popular among the environmental movement, he is the devil incarnate to many who would like to see big money out of politics. Some politicians used Steyer as a punching bag in the mid-terms, linking him with Obama as a environmentalist “jobs-killer”

Analysts note that Steyer flirting with running for office for years. He never rules it out, usually saying he’ll consider any option that provides him a platform for his top policy priorities, like climate change and promoting childhood education. When asked about his political ambitions back in 2013, Steyer said, “I am willing to do a lot of things to address the generational challenge we face. I will say that.”