Campaigning in Illinois on Saturday, Rick Santorum declared that if he wins the state's primary on Tuesday, he will capture the GOP nomination, reports NBC News.

"This is a primary, and turnout is everything. You do your job, you do your job, then this is the pledge," Santorum said. "If we're able to come out of Illinois with a huge or surprise win, I guarantee you, I guarantee you that we will win this nomination."

It's a bold claim, considering that Santorum is currently trailing Romney by an estimated 243 delegates and Illinois only awards 69 -- but perhaps the ex-Pennsylvania senator's campaign could use a little magical thinking in the face of such harsh delegate math.

Romney has long been favored in Illinois, where he is expected to benefit from a high number of affluent Republican voters in the Chicago area. But the southern, more conservative part of the state favors Santorum, and recent polls have shown a reasonably close race.

The Washington Post reports that Romney cut short his campaign trip to Puerto Rico to firm up his lead in the Land of Lincoln.

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