Charles Krupa, Associated Press
Republican presidential candidate former House Speaker Newt Gingrich shakes hands during a campaign stop in Hudson, N.H., Monday, Jan. 9, 2012.

MANCHESTER, N.H. — Newt Gingrich said he expects Mitt Romney to win Tuesday's New Hampshire primary. But with Romney's support slipping, the former House speaker argued that the race could end up being "wide-open."

Gingrich is preparing a blitz of television appearances and 11th-hour campaign stops Tuesday as he tries to whip up enthusiasm for his White House bid, following a disappointing fourth-place finish in Iowa. The former House speaker will visit polling places in Manchester, Bedford, Merrimack and Hollis.

Gingrich has used New Hampshire as a staging ground to launch more aggressive attacks on Romney, labeling the GOP front-runner timid and assailing his time at the helm of Bain Capital. The most successful elections, Gingrich argues, are those in which the contrast between the candidates is wide.

"I really do believe a Reagan conservative has a better chance of defeating (Democratic President Barack) Obama than a Massachussetts moderate," Gingrich said late Monday at a town hall at a high school in Hudson that drew some 500 people.

"I think you need a very clear, sharp distinction," he continued.

He's been stressing an economic message to cut taxes, slash regulations and promote an American-based energy policy. And he's even weighed in on some local issues, calling for better health care options for the state's veterans and speaking out against plans to place some 180 miles of electric transmission lines above ground in scenic areas in northern New Hampshire.

But even before New Hampshire voters cast a single ballot, Gingrich already was eyeing South Carolina, considered a critical state for the former Georgia congressman.

He's been fine-tuning his message, keying in on gun rights, veterans issues and abortion, which could prove pivotal in the nation's first Southern primary.

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