Republican presidential front-runner Mitt Romney has bounced back from midweek losses in three states to narrowly win Maine's caucuses, hours after winning a straw poll of Republican conservative activists.
Results of Maine's non-binding straw poll on Saturday showed the former Massachusetts governor with 39 per cent support, or 2,190 votes, ahead of libertarian Texas Congressman Ron Paul with 36 per cent or 1,996 votes.
Rick Santorum and Newt Gingrich, who did not campaign in Maine, won 18 per cent and six per cent of the vote, respectively.
Despite signs of higher voter turnout, the votes cast in Maine appeared to be only slightly above 2008 levels.
The outcome capped a good day for Romney, who unexpectedly lost to Santorum, a social conservative, in Missouri, Minnesota and Colorado on Tuesday to generate new doubts about his appeal to party conservatives. Republicans are seeking a nominee to challenge Democratic President Barack Obama in the November 6 general election.
Romney earlier won a closely watched straw poll at the Conservative Political Action Conference in Washington, with 38 per cent support to Santorum's 31 per cent.
More moderate than his rivals, Romney, a former venture capitalist, has struggled to convince conservatives he is one of them. He spoke to CPAC on Friday and called himself "severely conservative."
"I thank the voters of Maine for their support," Romney said in a statement after the Maine results. I'm committed to turning around America. And I'm heartened to have the support of so many good people in this great state."
In a sign of how seriously the Romney campaign took Maine and the potential for a fourth consecutive state loss, Romney flew to Portland on Friday for a town hall meeting, and spoke at two of the state's largest caucus sites on Saturday.
At a caucus in Sanford, Romney called Obama "a failed president" and added that he was "the one person in this race that can actually beat the president".
"I know what it will take to make America the best place in the world for job creation," Romney said.