Republican presidential hopefuls made the rounds in Iowa today, in a last-minute push before an expected 100,000 of the state’s residents visit the polls to cast the first votes to help determine who will be the Republican presidential nominee.

Though he had previously promised to keep his campaign “relentlessly positive,” former Speaker of the House Newt Gingrich lashed out at opponent Mitt Romney earlier today, over a series of anti-Gingrich ads that have recently aired on television.

Romney has claimed that he has no link to the political action committee producing the ads, but Gingrich isn’t buying it. When asked by CBS if he would call Romney a liar, Gingrich answered, “Yes,” adding, ”I think he ought to be honest with the American people and try to win as the real Mitt Romney and not a consultant-guided version that goes with talking points.”

Though unclear whether he will take the top spot in the Iowa caucuses, Romney has taken on a newly optimistic tone. ”We’re going to win this thing, with all of our passion and strength and do everything we can to get this campaign on the right track to go across the nation and to pick up other states and to get the ballots I need, the votes I need to become our nominee,” he said yesterday, during a stop at an Iowa asphalt plant.

Though the outcome of the caucuses remains difficult to predict, the winner is expected to be either Romney, Rick Santorum or Ron Paul.

Though somewhat of a dark horse, former Sen. Rick Santorum has suddenly made his mark on the race — surging in polls in recent weeks. Santorum has been criticized for being too hyper-conservative to win a presidential race, but, according to him, that’s exactly why he should be elected.

“You can ignore the pundit class,” he said during an Iowa campaign stop. “You can ignore the moderate Republicans, who say, ‘Oh we need a moderate. We’ve got to win, we’ve got to win.’ And Iowa will stand up and say: ‘No. We need to be principled to win.’”

Speaking to a handful of Fox News reporters this morning, Santorum called Paul (who has also experienced a surge in polls) “disgusting.” According to Fox, he also blamed Paul for Iowa robo-calls claiming that Santorum was pro-choice and against the Second Amendment.

Though the outcome of the Iowa caucuses is being stressed by nearly every national media outlet, it is important to point out that the winner doesn’t necessarily determine the outcome of the primary. As the Huffington Post points out, “Republicans aren’t allocating delegates on a winner-take-all basis.” The final Iowa delegates won’t be chosen for months, at the state convention.