PORTLAND, Maine - US Republican presidential front-runner Mitt Romney bounced back from midweek losses in three states to narrowly win Maine's caucuses on Saturday, hours after winning a straw poll of Republican conservative activists.Results of Maine's non-binding straw poll showed the former Massachusetts governor with 39 percent support, or 2,190 votes, ahead of libertarian Texas Congressman Ron Paul with 36 percent or 1,996 votes."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.He also brought some of his top surrogates, including son Tagg, to Maine to speak on his behalf.Sensing a possible victory, Paul hosted a party in Portland on Saturday evening. After the results were announced, he told supporters that Romney's margin of victory was so small, "it's almost like we could call it a tie."Paul also forecast that when Maine's delegates were finally assigned, "we will control the Maine caucus when we go to Tampa" for the Republican convention in August.Rick Santorum and Newt Gingrich, who did not campaign in Maine, won 18 percent and 6 percent 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 Nov. 6 general election.Romney earlier won a closely watched straw poll at the Conservative Political Action Conference in Washington, with 38 percent support to Santorum's 31 percent.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."