Rick Santorum is mocking Mitt Romney as a "Johnny come lately to the conservative cause."
Ahead of Wednesday night's GOP presidential debate in Arizona, Santorum told a tea party gathering in Tucson that Romney proposed a lower corporate tax rate only after Santorum had done so.
The crowd of 400 laughed and clapped when Santorum said America doesn't need a leader who has been "a well-oiled weather vane."
The former Pennsylvania senator urged Arizonans to support a courageous conservative rather than politicians who tell voters what they want to hear.
Santorum aimed his sharpest barbs at President Barack Obama. He said the president's economic plan is "more food stamps and government dependence."
Arizona's presidential primary is Tuesday.
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