PORTLAND — Mitt Romney hoped to avoid a fourth straight election setback Saturday in the GOP presidential nomination race, but feisty Ron Paul could extend that losing streak with a victory in Maine’s caucuses.

Romney, the one-time front-runner, stepped up efforts to court Republicans in recent days, reflecting growing concern about the outcome of what has become a two-man race in Maine.

Neither Newt Gingrich nor Rick Santorum, who won in Missouri, Minnesota and Colorado on Tuesday, is actively competing in Maine, where party officials planned to declare a winner Saturday evening.

Paul was optimistic as he greeted morning caucus-goers in Sanford, where a few hundred Republicans gathered in a nearly-filled high school gymnasium.

“I think we have a very good chance,” Paul said. Romney will “be better off if he wins it and I’m going to be a lot better off if I win. So this will give me momentum and it will just maintain his. It’s a pretty important state as far as I’m concerned.”

Romney wants Maine voters to help in his struggle to convince his party’s conservative wing that he should be the candidate they back. The former Massachusetts governor said in a Washington speech Friday that he was “a severely conservative Republican governor.”

He echoed that message in Sanford minutes after Paul left, and later in the day at a crowded Portland caucus.

“In my home with my mom and dad I learned conservative values,” Romney said. “I want to ask you and the people of Maine for your vote. If I get your vote, it’ll help me become our nominee. If I become our nominee, I’m going to beat this guy and bring America back.”

Paul, a libertarian-minded Texas congressman, is fighting to prove he’s capable of winning at all, particularly in a state where his campaign has focused considerable attention. He has scored a few top three finishes in other early voting states, but his strategy is based on winning some of the smaller caucus contests where his passionate base of support can have an oversized impact.

Paul suggested his candidacy was at a critical juncture. Asked whether he would stay in the contest until the GOP’s national convention in August, he answered: “I’m going to stay in as long as I’m in the race. And right now I’m in the race.”

There is no reliable polling to gauge the state of the Maine election, which drew fewer than 5,500 voters from across the state four years ago. But Romney’s recent activities suggest a victory is by no means assured, despite the natural advantages of being a former New England governor competing in a state he won with more than 50 percent of the vote four years ago.

He changed his schedule Friday night to add personal appearances at two caucuses Saturday; he had planned to take the day off.

Romney faced a rowdy crowd at a town hall-style meeting in Portland Friday night, where one heckler was removed by police. Others asked pointed questions about his off-shore bank accounts, feelings about the nation’s poor, and his continued support for the natural gas extraction process known as fracking.

On Saturday morning, he suggested that he’s the only one in the race who isn’t a Washington insider.

“I have never spent a day in Washington working,” Romney said. “I expect to go there, get it fixed, and then go home. I’m not going to stay in Washington.”

Some crowd members chanted, “Ron Paul,” as Romney left the crowded gymnasium.

Maine’s nonbinding presidential straw poll, which began Feb. 4, has drawn virtually none of the hype surrounding recent elections in Florida and Nevada, where candidates poured millions of dollars into television and radio advertising.

Romney and his allies spent a combined $15.9 million in Florida. But his campaign had placed only a small cable television ad buy airing Friday and Saturday, at a cost of several thousand dollars. But he sent surrogates to the state in recent days and hosted a telephone town hall in addition to Friday’s campaign stop.

Maine’s caucuses are spread over a week.

The state party will announce a winner Saturday evening, although a few contests will be held Sunday. Washington County, in the state’s far eastern region, postponed its caucuses until Feb. 18 because of a snow storm, disappointing some participants.

Helen Saccone, who’s from Lubec, said she understands that weather could create problems, but that those who wanted to caucus should have had the chance. “It’s Maine. Life goes on when it snows in Maine,” she said.

The rural region is likely stronger territory for Paul, who has been more active than Romney in the state.

Paul did reasonably well in Maine four years ago, earning more than 18 percent of the vote, and his support has grown since then in a state whose electorate isn’t afraid to support candidates outside the mainstream.

The tea party, hardly a Romney ally, has exerted significant influence, taking over the GOP platform and helping to elect Gov. Paul LePage.

“Paul needs to show he can win somewhere,” GOP strategist Phil Musser said. “My sense is a win in Maine for Romney would be nice. But to be honest, Ron Paul is camped out up there and he needs to win one.”

The timing of the contest also raises the stakes.

The narrative coming out of Maine will likely reverberate in the political echo chamber for weeks, given there isn’t another election until Arizona and Michigan host their contests Feb. 28. Romney hopes that narrative will be more positive than it has been over the last week, arguably his worst of the year.