Could New Hampshire hold the key? Romney and Obama take no chances.

President Obama and Gov. Mitt Romney are squeezing in some final visits to the Granite State to ensure that their voters’ support is rock solid come Tuesday.

New Hampshire may have just four Electoral College votes, but no one forgets that those could have won Al Gore the presidency in 2000. He lost here by just over 7,000 votes.

About 700,000 voters are expected at New Hampshire polls on Tuesday. There’s no early voting in the state, except by absentee ballot, so last-minute attention from the candidates can be key.

At a rally Saturday morning, Mr. Romney declared that “New Hampshire gave me the Republican nomination and New Hampshire is going to get me to the White House.”

Romney will return to New Hampshire on the eve of the election for what’s being dubbed the “Final Victory Rally,” a concert with Kid Rock.

“It speaks to how much Governor Romney really does treasure this state,” says campaign spokesman Tommy Schultz. “He began his campaign here….  In many ways it’s full circle coming back to where it started.”

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There’s more work cut out here for the Romney campaign, according to polls. As of Saturday morning, an averaging of recent polls by the website RealClearPolitics had Obama at 49 percent and Romney at 47 percent. The New York Times blog FiveThirtyEight by Nate Silver said Friday that Obama had a 77.8 percent chance of winning New Hampshire.

Still, amid a four-day flurry of visits to at least six states, Mr. Obama is slated to appear in Concord, N.H., Sunday morning. By his side will be former President Bill Clinton, who was busy pulling extra campaign duty this past week while Obama turned his attention to the aftermath of Hurricane Sandy.

There are two ways to interpret Obama’s 11th-hour appearance here, says Dante Scala, a political science professor at the University of New Hampshire. “Either things are worse than they look in the polls … or [organizers] are working from an excess of caution and they want to make sure that New Hampshire stays nailed down. I tend to think it’s the latter.”

Ads from both sides, as well as ads for tight races for governor and Congress, are saturating the airwaves. But “it’s the get-out-the-vote efforts that are going to be key to the final outcome,” says Andrew Smith, director of the UNH Survey Center.

Slightly more voters say they’ve been contacted by Democrats than by Republicans, but “the Romney campaign has got a ground game that’s a lot better than previous Republicans in New Hampshire,” Mr. Smith says.

Surrogates for both candidates have been making the rounds, too, trying to keep volunteers energized through the final days of knocking on doors and dialing the phone.

On Saturday, Caroline Kennedy is making a number of stops in what’s being billed as the “Granite State Women Decide 2012 Tour.” On Friday, Democratic National Committee Chair Debbie Wasserman Schultz kicked off that tour.

Since the spring, part of Obama’s strategy has been to “put social issues of concern to women, like access to contraception, on the front burner,” says Professor Scala.

That’s one of several issues that resonate in the state in part because of the controversial positions conservatives have pushed for in the legislature here, says Holly Shulman, spokeswoman for the Obama campaign in New Hampshire. These include defunding Planned Parenthood and limiting women’s contraception options.

“Granite Staters pay very close attention to their local politics, and Mitt Romney’s positions mirror that of the extreme legislature here,” Ms. Shulman says.

Women are also making the case for Romney, saying he’s focused on the issue that’s of biggest concern for women: the economy.

“In my circles, the economy, jobs, and quality education are on people’s minds,” says Laura Dodge, a stay-at-home mom from Bedford, N.H., who is volunteering for Romney. She knows people whose husbands have lost their jobs, and “they’re in a tough predicament…. Mom’s faced with the decision [of whether] to go back to work, but it’s hard when you’ve been out of the work force for so long.”

Other than the abortion issue, Ms. Dodge says she doesn’t see much difference between the candidates on women’s issues, but she likes that Romney “has been called up to situations before when he’s been able to turn things around,” such as the Olympics.

Dodge was part of a standing-room-only group of Romney supporters who came to Manchester Thursday afternoon to hear Republican Sens. Kelly Ayotte of New Hampshire and Marco Rubio of Florida. Both parents of young children, they painted a dramatic picture of the choice voters would be making Tuesday – and urged people to work hard to ensure they chose Romney’s fiscal responsibility and projection of US military strength.

Senator Rubio warmed up the audience by telling about his first trip to New Hampshire, campaigning for Bob Dole in 1996 by going door to door to hand out Florida oranges. Then he turned more serious as he talked about the need to preserve America’s free enterprise system, which makes it “unique to the history of the world.”

As the US-born son of Cuban immigrants, he said he could see more clearly how important it was to preserve the ability of people in the United States to move up from the station they are born into, through hard work and talent.

Romney will support that system, and will work for bipartisan solutions to problems, Rubio said. And if Romney doesn’t win, “we’ll lose some of what makes us exceptional.”

The troops indeed got a jolt of motivation. Rubio has “more style and charisma than anyone in the Republican Party – he embodies the American dream,” said Sean Cooper, a Massachusetts resident who hopes New Hampshire will swing Romney’s way.

The Obama campaign attracted some new volunteers for the get-out-the-vote effort after an Oct. 27 event in Nashua in which more than 8,000 people showed up to hear James Taylor sing as the opening act for an Obama appearance, says volunteer Jacob Swartz, a Massachusetts resident who is taking a semester off from Harvard to go door to door for the president.

“Being in a battleground state, there’s a lot of attention put here….  Everyone is so oversaturated with political ads … [but with] people who feel really strongly about the issues knocking on doors, you hope that measure of personal contact makes a difference,” says Mr. Swartz, who’s surrounded by Obama posters, white telephones, a life-size poster board cutout of the president, and fellow volunteers grabbing snacks as they put in long hours at the campaign office on Main Street in Nashua.

“New Hampshire is a good microcosm for the nation in a lot of ways,” Swartz says. “Economic issues are a concern, the social safety net. There are a lot of hard-working middle class people who just want everyone to be on a level playing field…. We hope we’re not waking up on the 7th to a change.”

In such a close race, it’s hard to know if there will be much impact from having other candidates on the ballot. Here in New Hampshire, Libertarian Gary Johnson and Constitution Party candidate Virgil Goode could siphon off some votes, says Linda Fowler, a government professor at Dartmouth College in Hanover.

The student vote could also make a difference, Professor Fowler says. A judge recently blocked an attempt by the legislature to make college students establish residency here in order to vote.

“We’re expecting a lot of attorneys to be engaging in poll watching to deny challengers the ability to intimidate students,” Fowler says.

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