MANCHESTER, N.H. -- The once-bursting 2012 Republican field is narrowing to a two-man race, and GOP voters have one month before casting the first votes to winnow it to one.

Barring a dramatic new turn, their chief options will be the steady but often bland demeanor of Mitt Romney and the idea-a-minute bombast of Newt Gingrich.

Herman Cain's suspension of his campaign Saturday, and Texas Gov. Rick Perry's continued struggles to regain traction, have focused attention on Romney, the former Massachusetts governor, and Gingrich, the ex-House speaker.

Romney has maintained a political infrastructure since his 2008 bid, especially in New Hampshire. Gingrich, whose campaign nearly collapsed months ago, is relying much more heavily on his televised debate performances and good will he built with conservatives in the 1980s and 1990s.

At a town hall meeting in New York sponsored by tea party supporters, Gingrich declined to characterize the race as a direct contest between himself and Romney.

Any of the GOP contenders could stage a comeback before the Jan. 3 Iowa caucuses, he said.

Romney seemed as eager as Gingrich to avoid casting the contest as anywhere close to decided. He repeatedly turned aside reporters' invitations to light into Gingrich, offering only gentle critiques.

"I don't think people have really settled down, in a final way, to decide who they're going to support in the nomination process," Romney told reporters in Manchester, where he held a rally and knocked on a few doors. "I hope they give us a good, careful look."

That was about as much emotion and daring as he showed all day. With the second-tier candidates ramping up criticisms of Gingrich, Romney stuck to his steady-as-she-goes style of criticizing President Barack Obama's economic record, and saying little else.

Newt Gingrich has taken the lead in a poll of Republican voters in Iowa, followed by Ron Paul and Mitt Romney.

Former House Speaker Gingrich received support from 25 percent of likely voters in the leadoff Iowa caucus, while Texas Rep. Paul had 18 percent and former Massachusetts Gov. Romney recorded 16 percent in the Des Moines Register's Iowa Poll released Saturday.

The new poll of 401 likely Republican caucusgoers has a margin of error of plus or minus 4.9 percent.