It’s finally here. After months of Republican campaigning, voters will finally weigh in. On Tuesday, the candidates got vicious, with Rick Santorum calling Ron Paul "disgusting" and Newt Gingrich labeling Mitt Romney a "liar." Romney, Santorum, and Paul are reportedly in a three-way tie for first in recent polls. A win for Romney, who is expected to take New Hampshire next week, may mean he’ll close out the GOP nomination early. But surging Santorum and Paul can complicate things with a surprise victory. Things could be tricky: Iowa’s rules allow for voters to register Republican in the 11th hour to join in on the caucus fun—meaning Democrats and independents could have some say tonight. While Iowa usually knocks out candidates who are ill prepared, it’s important to note that in 2008 Mike Huckabee won. CNN announced that Paul and Romney led the entrance polls, with Santorum following close behind. The polls also revealed that 37 percent of caucusgoers made their decision in the last "few days," while 12 percent made up their minds today.