GOP candidates look to New Hampshire Mitt Romney headed to New Hampshire on Wednesday to shore up support in the northern state for his Republican presidential bid, just hours after clinching a narrow victory in the Iowa caucuses. Mr Romney won in Iowa by just eight votes over Rick Santorum, the evangelical candidate who appealed to the state's social conservatives, making the caucuses the closest presidential nomination contest in recent US political history. Thank you, Iowa! What better place than the heartland of America to start the restoration of America's heart and soul," Mr Romney tweeted in the early hours of Wednesday morning. The former Massachusetts governor won with 30,015 votes while Mr Santorum, a former Pennsylvania senator, was a whisker behind with 30,007 votes. Both had roughly 25 per cent of preferences. Ron Paul, the libertarian Texas congressman, came in third with 21 per cent of the vote. Newt Gingrich finished fourth with 13 per cent, Rick Perry fifth with 10 per cent and Michele Bachmann trailed with 5 per cent. Following her poor performance, Ms Bachmann announced at a press conference in Iowa on Wednesday that she was pulling out of the race. Her sixth place in the caucuses was a sharp turnaround from a few months ago, when she won the influential Ames straw poll. Ms Bachmann had previously cancelled plans to campaign in South Carolina. Her withdrawal is likely to benefit Mr Santorum as both appeal to social conservatives, evangelical Christians and Tea Party supporters. That will not make much difference in New Hampshire, but could give Mr Santorum a boost in South Carolina, which is socially conservative like Iowa. There was also speculation Mr Perry might abandon the race in the coming days after the Texas governor said he was going home to assess the future of his campaign. The Iowa caucus is the first step in the Republican nomination process, followed by the New Hampshire primary next Tuesday. As the former governor of a neighbouring state and someone who owns a holiday home in New Hampshire, Mr Romney is coming first in the polls and is expected to win there. He will hold a town hall meeting at Manchester Central High School at lunch time on Wednesday. Mr Romney had not campaigned heavily in Iowa, where he spent millions of dollars in 2008 only to come in a humiliating second, and was satisfied with the result. In his speech, he stuck to familiar criticism of President Barack Obama on the economy and national security and looked ahead to the next contest on January 10 in New Hampshire, where he holds a commanding lead in the polls. "Let's get that job done," he said. His campaign was bolstered by the announcement after the caucus that John McCain, his once-bitter foe and the 2008 Republican presidential nominee, would endorse him. However, Mr Santorum's strong showing illustrates the volatility of the Republican electorate, meaning the race could still see new twists and Mr Romney may not rapidly sew up the nomination "You, by standing up and not compromising, and being bold - and leading - you've taken the first step of taking back this country," an emotional Mr Santorum said after cementing a stunning comeback from single-digit support earlier in the race. Mr Santorum, who was also headed to New Hampshire on Wednesday, benefited from a late surge in enthusiasm for his bid among social conservatives. Craig Robinson, a party veteran and writer of the influential blog Iowa Republican, said that Mr Santorum's traditional grassroots approach - campaigning in all 99 counties in the state - had worked. "Santorum's strategy paid off, largely because Iowa's plentiful social conservatives coalesced around his candidacy in the closing days of the campaign," Mr Robinson wrote. His message on bringing manufacturing jobs home resonated with blue-collar workers. Another key factor behind Santorum's stunning victory in Iowa is the simple fact that he made himself more assessable to Iowa voters than any other candidate. Speaking at his campaign headquarters after his third-place finish was confirmed, Mr Paul seemed emboldened by the vote, despite trailing Mr Santorum and Mr Romney by a handful of percentage points. We have a tremendous opportunity to continue this momentum. We're going to continue scoring just as we did tonight," he said, as he vowed to continue his pursuit of "liberty" and a "wise foreign policy." Mr Gingrich, the frontrunner in Iowa just a month ago before being damaged by a slew of attack ads, swore to keep fighting in New Hampshire and beyond despite his fourth place finish. In his speech, he took aim at both Mr Paul for his anti-war stance and Mr Romney for being too moderate. "We're not going to go out and run nasty ads, but I do reserve the right to tell the truth," he said. The partial results confirm that Republican voters - at least in Iowa - are still divided in their search for their preferred candidate to challenge Mr Obama's hold on the White House in November's general election. A win in Iowa is considered a boon for candidates vying for the presidency, in that it helps build political momentum and fundraising for the rest of the campaign. Conversely, a poor showing raises the stakes for a better performance in the next early contest in New Hampshire next Tuesday, and could even lead some candidates to drop out, winnowing the field. Mr Obama's re-election campaign said that the message from Iowa was that Republican voters could not decisively get behind any one candidate. "Who exactly leads the Republican race going forward isn't clear, but we do know two things," wrote Jim Messina, Mr Obama's campaign manager, in an email to supporters on Wednesday morning. The "extremist Tea Party agenda won a clear victory" by forcing all candidates to embrace its agenda, he said, adding that Democrats could expect an onslaught of unprecedented spending from outside "super-PAC" groups. The influence of the new groups was laid bare in Iowa, where candidates" supporters spent almost $16m, much of it on negative attack ads against each other.