As they await an Illinois primary vote whose outcome is hardly assured, Mitt Romney is betting his message of economic proficiency will resonate with Republican voters more than Rick Santorum’s sharply honed conservatism.

Both men were competing for the 54 delegates at stake Tuesday in Illinois. They were looking to score a victory in a state that was not only home to President Obama, but is also one of the last major battlegrounds before a three-week lull in April.

Tuesday’s primary comes on the heels of Romney’s overwhelming victory Sunday in Puerto Rico, a territory Santorum courted at the expense of spending time in Illinois.

Though Illinois is expected to be far closer than Puerto Rico, recent polls indicate Romney may be pulling away.

Even if he should lose the popular vote, Romney is poised to win the delegate battle. Santorum cannot win at least 10 of the state’s 54 delegates available Tuesday because his campaign didn’t file the necessary paperwork.

Romney’s confidence was on display Monday, while Santorum was forced on the defensive for first declaring that the economy was not a top issue in the campaign and then stating that “the campaign doesn’t hinge on unemployment rates.”

By day’s end, Santorum had conceded that the economy and unemployment were important but said they were symptoms of what he described as broader ills: government intrusion and eroding freedom.

Romney on Tuesday denounced Obama’s economic policies, choosing to make his remarks at the very university where the president once taught constitutional law.

Santorum hit hard at Romney, who leads the Republican field in delegates and whose nomination, barring a political disaster, seems more and more assured as the contest results mount. Santorum cloaked himself in the mantle of Ronald Reagan and argued that health care, not the economy, is the predominant issue of the campaign.

Santorum and Romney crisscrossed the state Monday, coming within mere hours of each other in Peoria.

Romney planned to hold an election-night party Tuesday in Schaumburg, Ill.

Santorum was leaving the state to deliver an evening speech about Abraham Lincoln in Gettysburg, Pa. Last week in Chicago, Obama said he hoped the Republican candidates would “take a little time to reflect” on Lincoln while campaigning in Illinois.

After Tuesday, the contest moves to Louisiana, in a part of the country where Romney has had trouble breaking through. Louisiana has a total of 46 delegates to the Republican National Convention, but only 20 delegates are at stake in Saturday’s primary. An additional 23 delegates will be selected at the party’s state convention in June, and the remaining 3 are the automatic RNC delegates.

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