In a Friday tweet Trump says, "John Cox is the man - he'll be the best Governor you've ever had."
RELATED: California governor debate focuses on housing, gas tax
Cox is facing off against Republican Assemblyman Travis Allen and several Democratic candidates in the primary. Lt. Gov. Gavin Newsom, a Democrat, is the odds-on favorite to win June 5, but Republicans hope that the remaining Democrats will split the vote enough to allow one of the GOP candidates onto the ballot in November.
Cox has said he voted for Libertarian Gary Johnson in the 2016 presidential race, but has also said he regrets that vote.
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California finally deserves a great Governor, one who understands borders, crime and lowering taxes. John Cox is the man - he’ll be the best Governor you’ve ever had. I fully endorse John Cox for Governor and look forward to working with him to Make California Great Again!— Donald J. Trump (@realDonaldTrump) May 18, 2018