January 02, 2012, 12:00 PM EST

By Lisa Lerer and John McCormick

(Updates with Romney comment in third paragraph and poll in second to last paragraph. For more campaign news, see ELECT.)

Jan. 2 (Bloomberg) — Republican presidential candidate Mitt Romney worked to build support before friendly crowds while rivals attempted to unify a splintered vote within their party as they campaigned across Iowa’s snow-dusted fields.

In the final full day of campaigning before the state’s caucuses, Romney limited his stops to counties where he gained strong backing during his failed 2008 presidential bid. As he has for days, he largely ignored his competitors, keeping his attacks focused on President Barack Obama.

“Boy, this county was good to me last time around,” Romney told a crowd gathered this morning in Davenport, Iowa. “I need you to get out and do that again with even more votes. Get out and vote, vote, vote.”

The former Massachusetts governor is playing it safe before Iowa’s Jan. 3 contest, recognizing that even without coming in first he’ll probably emerge from the state in a strong position.

Recent polls indicate that Romney has a good chance of winning tomorrow. A victory would position him to do well in New Hampshire, where he’s been a clear leader. No Republican who has won both states, host to the first two tests in the nominating contest, has failed to become the party’s candidate.

“I can’t tell you who’s gonna win this thing, but I do believe that I’m gonna have a great deal of support and that that will give me the kind of boost I need as I go into a season of a number of other states,” he told reporters in Atlantic, Iowa yesterday.

Question Viability

A loss in Iowa would give opponents a chance to question his viability. Still, Romney is so well positioned in New Hampshire, a state his campaign views as its firewall, that he could survive the defeat.

While surveys show that a majority of Republican primary voters nationally are still searching for an alternative to Romney, they’ve failed to rally around an individual candidate. That gives Romney an opening to do well in Iowa, even if he’s unable to capture a majority of the vote in the state.

The Iowa Poll by the Des Moines Register newspaper, released on Dec. 31, showed Romney with the support of 24 percent of likely Republican caucus-goers. Ron Paul, a Texas congressman, had the backing of 22 percent. Rick Santorum, a former U.S. senator from Pennsylvania, secured 15 percent after a surge in the final two days of sampling.

Still, 41 percent of survey participants said they could change their minds.

‘Wide Open Race’

“It is a wide open race,” said Iowa Governor Terry Branstad, a Republican, during an interview on “Fox News Sunday.” “Any of the candidates potentially could win here.”

As Romney carefully campaigns, his rivals are working hard to consolidate the support of Republicans who doubt his fiscal and social conservative credentials.

“This is your chance heartland, this is your chance heartland of America to speak out,” Santorum told a crowded coffee shop in Sioux City, Iowa yesterday.

Surrounded by voters and reporters, Santorum predicted that he would do well in the state because “folks in Iowa understand” that the “key to America, the foundation of America, are strong families and strong faith.”

Santorum and his closest rival, Paul, went directly at one of Romney’s chief arguments: that he is the strongest positioned to beat Obama in the general election in the fall.

Diverse Coalition

Romney and his supporters argue that both Paul and Santorum would be unable to build the diverse coalition of voters necessary to win the White House. Santorum has strong backing among evangelical Christians, and Paul draws his support largely from staunchly fiscally conservative voters.

During an interview yesterday on CNN’s “State of the Union” program, Paul dismissed rival criticism that he could not be elected in a general election against Obama.

“I was elected 12 times once people got to know me in my own congressional district,” he said. “I think that might be propaganda more than anything else.”

Santorum also cited his own political background as proof of his viability.

“I’m the candidate that actually was able to win in states, as a conservative, in getting Democrats and independents to vote for us,” Santorum said in an interview on CNN. “Mitt Romney has no track history of doing that.”

Direct Swipe

Gingrich, who’s fallen in recent polls, took a more direct swipe at Romney yesterday, accusing him of buying his way into the White House.

“Romney would buy the election if he could,” Gingrich told reporters after attending Mass yesterday at the St. Ambrose Cathedral in Des Moines.

In an interview with Fox News, Gingrich blamed his dramatic recent drop in polls on millions of dollars in negative advertising by an outside group with ties to Romney, whom he derided as a “Massachusetts moderate” who would not fare well as the race heads into southern states later this month.

In Atlantic, Romney touted his record as governor of Massachusetts, saying he led with “good, solid conservative principals.”

He criticized Santorum, noting that the former Pennsylvania senator endorsed him during the 2008 campaign.

“I can tell you that our backgrounds are quite different,” he said. “Like Speaker Gingrich, Senator Santorum has spent his career in government, in Washington — nothing wrong with that. But it’s a very different background than I have.”

Five-Hour Journey

After meeting voters in western Iowa yesterday, Romney drove directly across the state for events in Davenport and Dubuque. The five-hour journey kept Romney in the two population-rich flanks of the state, where he did well in 2008.

Addressing supporters gathered at a dance hall in Davenport, Romney was joined on the stage by his wife, Ann, his brother, Steve, and three of his five sons.

“People are starting to figure out that this is the guy that’s going to beat Barack Obama,” said Ann Romney. “We’re loving the turnout.”

In interviews on news programs yesterday morning, Minnesota Congresswoman Michele Bachmann, too, cast herself as having the strongest conservative credentials.

Bachmann, in interviews on ABC’s “This Week” and “Fox News Sunday,” argued that she’s won “thousands” of converts in recent days with a tour of Iowa’s 99 counties.

’Core Conservative’

“I’m the strongest core conservative in this race,” Bachmann said on “This Week.” Perry argued on Fox that he would appeal to people looking for someone who’s an “outsider” that doesn’t hail from Washington or Wall Street.

Both plan to head directly to South Carolina after the Iowa caucuses, skipping over New Hampshire. Their travel schedules suggest they see little chance of making significant strides against Romney in the granite state.

Romney has a commanding lead in New Hampshire, according to a Suffolk University/7NEWS two-day tracking poll of likely voters in the state released today. The survey showed Romney leading with 41 percent of the vote followed by Paul, at 15 percent, Gingrich at 11 percent and former Utah Governor Jon Huntsman at 11 percent.

“I don’t know who’s going to win, but I think we’re going to have good support,” Romney said in Atlantic. “And then on to New Hampshire, South Carolina, Florida, Nevada, boy it’s going to be a terrific race.”

–With assistance from Tim Higgins in Sioux City, Iowa and Kristin Jensen in Washington. Editors: Justin Blum, Mark Silva

To contact the reporters on this story: Lisa Lerer in Council Bluffs, Iowa at llerer@bloomberg.net; John McCormick in West Des Moines, Iowa, at jmccormick16@bloomberg.net

To contact the editor responsible for this story: Mark Silva at msilva34@bloomberg.net