ATLANTIC, Iowa - Mitt Romney for the first time today attempted to draw a clear contrast between himself and Rick Santorum, who has seen a recent surge in Iowa polling, suggesting that the former Pennsylvania senator fits the bill of a career politician who has less of an understanding of the economy than he does.

"I can tell you that our backgrounds are quite different," said Romney, responding to a reporter's question about appealing to voters choosing between him and Santorum. "Like Speaker Gingrich, Senator Santorum has spent his career in government, in Washington - nothing wrong with that, but it is a very different background than I have.

"I think the people of this country recognize that with our economy as the major issue we face right now that it would be helpful to have someone who understands the economy firsthand," Romney said.

A Des Moines Register poll of likely Republican caucus-goers released Saturday evening found Santorum rising in the final two days of the poll to within points of Romney - edging out Ron Paul for a second place finish. Overall, the poll found Romney leading with 24 percent support, followed by Paul with 22 percent and Santorum with 15 percent.

While Romney remained outwardly positive about Santorum today - referring to him as a "good guy" who has "worked hard" - the former Massachusetts governor also made sure to defend his own record as a conservative.

"I'll let people make their own assessment of our respective records, but I'm a conservative," Romney said. "I'm proud to be a conservative businessman, and I think what distinguishes me from the others in the field is that I understand the economy first hand, having lived in it."