Santorum's new attack ad on Romney is dirty

A new ad by the Rick Santorum campaign airing in Michigan portrays Mitt Romney as a mudslinger. There's a Romney look-a-like literally shooting what appears to be mud out of an assault rifle (which is actually a paintball gun as a helpful reader points out).

"Romney's negative attack machine is back in full throttle," a voice over in the ad says. "This time Romney's firing his mud at Rick Santorum." An awkward turn of phrase, if you know about Santorum's Google problem.

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