SACRAMENTO (KCBS)— Lt. Governor Gavin Newsom says he will not run for the U.S. Senate seat that Barbara Boxer will give up in 2016. According to a post on his Facebook page, Newsom says, “It’s always better to be candid than coy”, which is why he’s revealing now that his head, heart and unfinished work all remain firmly in the State of California.

Sonoma State Political Science professor David McCuan said the takeaway is that Newsom would rather run for governor in 2018 when Governor Brown steps aside.

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“He has an executive mentality,” said McCuan “He’s not someone who might be able to go along, and get along in the Senate. I mean he certainly could adapt his style, but also he has a much more executive like mentality in terms of getting things done, trying to lead the conversation.”

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Newsom’s decision leaves Attorney General Kamala Harris as the most formidable potential 2016 candidate. By late Monday, several sources claimed that her advisor said she plans to announce her bid on Tuesday. Earlier in the day, Harris declined to comment on what exactly her plans were.

Two knowledgeable sources told KCBS, Newsom and Harris did not make a deal, or even have a direct discussion, about who would run for what.

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KCBS has also learned that East Bay Congressman Eric Swalwell is now looking at making the race, as are former Los Angeles Mayor Antonio Villaraigosa, Congressman John Garamendi and former Congresswoman Ellen Tauscher. Two former Republican state chairmen, Duf Sundheim and Tom Del Beccaro, have thrown their name in the hat as well.