FRANKSVILLE, Wis. -- What started as a good day for Rick Santorum took an abrupt turn on Sunday after the GOP presidential candidate grew frustrated with reporters asking him to clarify his remark that Mitt Romney is the worst Republican in the country to take on President Obama.

During his final campaign stop of the day here, Santorum said of Romney, “Pick any other Republican in the country, he is the worst Republican in the country to put up against Barack Obama." The comments, Santorum would clarify, were in reference to the similarities between Romney's and the president on the issue of health care. It is a common critique he levels against his chief rival, but never has the former Pennsylvania senator called Romney the "worst Republican in the country" to go head-to-head with the president.

When pressed by reporters to clarify his statement, Santorum said, “On the issue of health care. That’s what I was talking about, and I was very clear about talking about that. OK? Come on guys, don’t do this. I mean you guys are incredible. I was talking about Obamacare, and he is the worst because he was the author of Romneycare.”

But the questions struck a chord with Santorum, and when he faced the same question again, he used a profane word and accused the media of "distorting" his speech.

However a press release sent out from the Santorum campaign shortly after the rally here seemed to double down on the candidate's comments. "Rick Santorum spoke plainly and clearly that of all the Republicans in the field, Mitt Romney is the worst possible candidate to take on Barack Obama, because Mitt Romney authored the blueprint for Obamacare and the issue of healthcare would be off the table," the release said.

Santorum has done a lot of clarifying lately, with recent comments suggesting Obama would be a better choice than Romney in a general election and saying the unemployment rate will not affect his campaign. In both cases, he accused the media and his opponents of taking his words out of context. But in both cases, the Romney campaign used his own words against him.

Sunday's remarks were no exception, with Romney spokesperson Ryan Williams telling reporters, “Rick Santorum is becoming more desperate and angry and unhinged every day...He’s panicking in the final stages of his campaign.”

Before his last event, Santorum had been all smiles on the trail the day after receiving nearly double the amount of support Romney did in the Louisiana primary.  Along with two rallies today, the GOP hopeful also fit in brunch at the Machine Shed and, for the second time in as many days, a few frames of bowling. In an earlier rally in Fond du Lac, WI, Santorum drew an overflow crowd.

But by Sunday's end, Romney advisers were using the hash tag "Tantorum" to draw attention to past instances of the former senator losing his cool. The response blasted out by the Santorum campaign no mention of his use of a not so family friendly word.

Santorum heads to Washington, DC where he will spend Monday before returning to the Badger State later in the week.