Santorum explains his change of heart regarding Romney

Mitt Romney's presidential campaign gleefully released a video last week of Rick Santorum endorsing him for president in 2008, when Santorum called Romney "the conservative" in the primary that year.

"If you want a conservative as the nominee of this party," Santorum said at the time, while Romney stood behind him, "you must vote for Mitt Romney." But as Romney's chief rival four years later, Santorum has gone from praising him as the only conservative in a Republican primary to blasting him as a "moderate" who is "uniquely disqualified" to debate President Barack Obama in the general election.

But Romney was not in office from 2008 to 2012 and thus didn't exactly implement legislation that could be scrutinized as too moderate. So why the change of heart?

Santorum says it was a matter of betrayal.

"What Governor Romney did was betray what he said he was going to be," Santorum told reporters after a rally in Illinois on Monday. "He said he had reformed. He said he was going to be a conservative. Then he went out and proposed and supported the Wall Street bailouts, now he goes out and defends the Romneycare proposal, which is clearly a failure, and one that was clearly a model for Obamacare. And he went out and advocated for his program to be the model for Obamacare."

When asked if he was trying to stretch out the primary, Santorum said he has no plans to dip out "anytime soon."

"Did I give anybody the impression that I'm getting out of this race anytime soon?" he said, turning his attention directly to a group of reporters who have followed him on the campaign trail for months. "I'm not too sure you guys are quite getting the flow of this yet. Just hang in there with us, okay? We'll be around for a while. We'll all have gainful employment for the time being."

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