Rick Perry is Mitt Romney's tool.
What else could explain why he's constantly going after all of Romney's opponents? Herman Cain, Newt Gingrich, now Rick Santorum. Never the front-runner; only ever the challengers. Someone's trying for the old Massachusetts-Texas alliance.
But why would Rick Perry support a liberal from Massachusetts? Because he's an old-fashioned, unreconstructed totalitarian liberal, like Lyndon Johnson, and his personal hero, Al Gore.
Perry was the first candidate to take it to Romney.
Correction: Perry did run one attack ad at least on Romney... over an issue everyone already knew about: Obamacare. But check out the way that the two words that are played with in the ad are “Care” and “Believe” Seriously, Rick Perry’s “attack ad” on Mitt Romney leaves you with the message, “Mitt Romney... Believe” with a voice saying, “He’s right.”