As former House speaker Newt Gingrich surges in the Republican presidential primary polls, longtime New Hampshire favorite Mitt Romney returned to the state Saturday to try to convince residents that he is not taking their votes for granted.

In a stark contrast to Gingrich, who confidently predicted in an ABC News interview Thursday that he would be the party’s nominee, Romney’s team handed out buttons that read “earn it” at an early morning rally in the parking lot of a Manchester pizza parlor as supporters readied for a day of door knocking.

And, to prove the point, Romney joined volunteers in a bit of old-style New Hampshire campaigning that has become rare as campaigns have relied increasingly on television appearances and glossy debates — walking Chestnut and Trenton streets in north Manchester, knocking on doors and meeting voters.

“This is a primary to be won by the person who’s willing to put the effort and shoe leather to get the job done,” he said after visiting about a dozen homes, warmly greeting residents who came to the door and leaving literature if no one was there.

The exercise was an acknowledgment that despite Romney’s tenure as governor of neighboring Massachusetts and his years spent campaigning in New Hampshire, a victory in the first-in-the-nation primary on Jan. 10 is not assured.

“We’re going to have to do an awfully good job to win this thing. It’s not going to be just given to us,” he told a cheering crowd of volunteers outside Theo’s Pizza, as he stood in the bed of a silver 2008 Dodge Ram pickup with former Minnesota governor Tim Pawlenty.

Over the years, Romney has been dogged by stories of his awkward interactions in this kind of retail politics. This week a C-SPAN video of a painfully earnest Romney greeting voters at a diner in Waltham, Mass., while running for the U.S. Senate in 1994 went viral in the political world.

But in jeans and a casual black jacket, on a chilly but clear and sunny morning, Romney appeared at ease in Manchester on Saturday.

Standing on the wrap-around porch of one home, as a saw buzzed periodically in the background, he talked home repair with Mike Bombara and wife Amanda, marveling that the couple are using a cement siding to restore their home to its original 19th-century appearance but with modern durability.

A recent transplant from Florida, Bombara and his family had not been on Romney’s list to visit for the day. But he crossed the street to take pictures with the couple and their two children when they came out to gawk at the sight of the former governor, surrounded by a mass of television cameras, strolling slowly up their street.

“It was very normal — just like talking to one of the neighbors,” Bombara, 38, said of the exchange. He added that he is still registered in Tampa and plans to vote for Romney in the Florida primary.

In another driveway, Romney goofed around with a 3-year-old wearing a puffy coat with a fur-edged hood, as the boy batted at a ball with a plastic bat.

“So, Charlie, will you be voting in the Republican primary?” Romney said to the boy, drawing a laugh from his father, longtime supporter Bill Skouteris.

On the porch of a picturesque white clapboard home with green shutters, he joked about his family’s Christmas card with Liz Feren — who told Romney she would be a “worker bee” to help get him elected. “Have you gotten it yet this year?” he asked her. “No,” she said, before immediately adding, at Romney’s obvious chagrin, “Don’t sweat it!”

After disappearing briefly into the home of another man, he emerged after a few moments and announced brightly, “Look what we found in the basement.” It was a sign left over from Romney’s 2008 run for president. Romney helped the man tack it into the ground.

Part of the effort was intended to show off Romney’s long ties to the state and his well- oiled New Hampshire organization. His campaign said 500 volunteers would knock on 5,000 New Hampshire doors and make 12,000 phone calls on what they called Super Saturday.

Romney blunted criticisms he’s offered in recent days of Gingrich, instead promising he’d keep giving primary voters the opportunity to get to know his background better.

“Over the last year, there have been various people who have surged,” he told reporters. “I’ve been steady throughout the storms.”