SACRAMENTO (CBS/AP) — Former U.S. Secretary of State Condoleezza Rice is endorsing investment banker Neel Kashkari’s bid for California governor amid growing concern within the party about his GOP rival.

In an endorsement note sent Wednesday, Rice says Kashkari is focused on “uniting Californians around fiscally conservative economic principles.”

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She says the GOP must support policies that “make opportunity and the American dream more accessible for all.”

It’s a subtle reference to the battle playing out between Kashkari, a moderate former U.S. Treasury official in the Bush administration, and Assemblyman Tim Donnelly, a tea party favorite who is leading in polls for the June 3 election.

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Rice is a professor at Stanford University and among the most popular figures in the GOP. Many California Republicans had hoped she would run for governor herself.

In a statement, Kashkari said, “It’s an honor to have such a principled conservative who shares my hopes for creating a better California announce her support of my campaign. Secretary Rice agrees that we need a fresh perspective in Sacramento and like me, she believes in growing the Republican Party in California and across the U.S. based on fiscal conservative principles.”

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