And then he spent the entire post-speech press conference walking back from that statement.

CBS:

After a rally at the South Hills Country Club here, Santorum asked Republicans to "pick any other Republican in the country" than GOP presidential front-runner Romney, based on issues that make the former Massachusetts governor "uniquely disqualified" to run against Obama.

Reporters swarmed him for clarification, only to have Santorum testily reply that it was unreasonable to take his comment outside the context of health care.

"I would say, as for, on the issue of health care, yes, that's what I was talking about - Obamacare, as you heard me say," he said. "That's what I said. I didn't say anything different than that. That's exactly what I said."

Minutes later, Jeff Zeleny of The New York Times followed up with a question about his outburst, to which Santorum asked, "What speech did you listen to? Stop lying."

Pressed further, Santorum clarified that he meant Romney was the worst candidate "to run against Barack Obama on the issue of health care, because he fashioned the blueprint. I've been saying it in every speech. Quit distorting our words. If I see it [in print], it's bull(expletive). C'mon man, what are you doing?"

Romney spokesman Ryan Williams quickly issued a statement in response: "Rick Santorum is becoming more desperate and angry and unhinged every day. He see conservatives coalescing around Mitt Romney and he's rattled by the backlash caused by his suggestion that keeping Barack Obama would be better than electing a Republican. He's panicking in the final stages of his campaign."

Using barnyard language is not the best way to present yourself as a credible presidential candidate. And if you're going to criticize your rival, you can't make a blanket statement and then come back later and say you only meant it in the context of health care reform.

Santorum has made a couple of gaffes in recent days that suggest he's losing concentration and lashing out uncontrollably at Romney. This only helps Romney contrast his cool demeanor with Santorum's anger.

People don't elect angry people president.