Romney and Santorum slug it out in Iowa Reporting from Des Moines, Iowa - In the closest finish in the history of the Iowa caucuses, Rick Santorum and Mitt Romney wound up in a virtual dead heat in the first battle for the Republican presidential nomination. The Texas governor, who started as a prime contender for the nomination last summer, broke off plans to fly to South Carolina for more campaigning, and said he was returning home instead to "determine whether this is a path forward." Santorum rode a late-breaking burst of support after getting counted out by virtually everyone until the final days of a long campaign. "Thank you so much, Iowa," said the former Pennsylvania senator, who swapped his trademark sweater vest for a coat and tie to address jubilant supporters in a Des Moines suburb. Romney, addressing supporters at a downtown hotel, congratulated Santorum and Ron Paul, who finished third. "We also feel it's been a great victory for us, as well," he said. Paul, nearly doubling his Iowa vote from 2008, was a close third. In an otherwise upbeat speech to supporters in the Des Moines suburbs, the Texas congressman said that he and Romney were the only top-tier vote-getters "who can actually run a national campaign and raise the money" - a clear shot at Santorum. But his failure to finish higher disappointed many of his supporters, the dejection evident on the face of his son and political heir, Sen. Rand Paul (R-Ky.), who stood behind him onstage. Only slightly more Republicans turned out as in 2008. But the lack of a compelling social conservative to excite the Christian conservatives who dominate the caucuses, and a late-starting push by Romney, who played down his Iowa campaign until the last six weeks, may have been contributing factors. Despite the close result, there is no official provision for a recount because no delegates are at stake. The Republican vote was essentially a popularity contest among those who attended, and at some caucus sites there are no paper records of the vote. The results were a clear setback for a pair of candidates once expected to contend for the nomination - Perry and Newt Gingrich. Michele Bachmann, who won a high-profile Iowa straw poll last August, was a distant sixth and faces elimination from the race, though she gave no indication in election-night comments that she would drop out. With Romney hoping to put an effective lock on the nomination as soon as the end of this month, the Republican race will now enter a new, more contentious phase. That seemed clear in Gingrich's withering election-night remarks. The former House speaker - who has been subjected to a fusillade of negative attack ads - lashed out at Romney, a man he had labeled as a liar in a broadcast interview earlier in the day. Standing before his supporters, his wife Callista at his side, Gingrich called Romney "a Massachusetts moderate who in fact will be pretty good at managing the decay" in America. Gingrich said Romney had given "no evidence" of an ability to change the culture or politics of the country. A caucus-night survey of hundreds of Iowans as they entered voting sites across the state showed that Romney, the caucus runner-up during his first presidential try four years ago, split with Santorum the votes of those who identified themselves as Republicans in a survey of hundreds of caucusgoers as they entered voting sites across the state. Romney also was the first choice of those who said they prized business experience over a career in government, a group that made up two-thirds of caucusgoers. Paul drew strong support from independents and those under 30, many of them first-time caucusgoers. Santorum drew support from social conservatives, who cast about 3 in 5 votes, virtually the same share as in 2008, when Mike Huckabee, an evangelical Christian favorite, was the Iowa winner.