1 of 2
Eric Gay, Associated Press
Republican presidential candidate, former Massachusetts Gov. Mitt Romney shakes hands with former House Speaker Newt Gingrich after a Republican presidential debate in Sioux City, Iowa, Thursday, Dec. 15, 2011.

DES MOINES, Iowa — As their rivals look for support among Iowa caucusgoers, Mitt Romney focused on early voting South Carolina and Newt Gingrich stayed close to home in Washington with a little more than two weeks before this state starts the winnowing of the Republicans' presidential hopefuls.

Michele Bachmann and Rick Perry both continued bus tours through rural Iowa, while Rick Santorum continued an all-in strategy that has won him the honor of spending the most time in the state yet has not yet translated that into support in polls. Ron Paul, who has a loyal following among his party's libertarian wing, continued to build momentum and organization here; he does not have public events scheduled until midweek, though.

Ahead of Jan. 3's lead-off contests, caucusgoers remain incredibly undecided and most candidates are redoubling efforts before voters largely tune out the race for the week between Christmas and New Year. Televisions in Iowa are already laden with political advertising and the final weeks of the campaign are expected to escalate their frequency.

Gingrich, who faces the toughest criticism on the airwaves, planned a conference call with reporters on Saturday and then an appearance on CBS' "Face the Nation" on Sunday. As caucus day comes closer, the former House speaker's decision to effectively take the weekend off raised eyebrows given his rivals' busy schedules to meet as many voters in this state as possible.

Gingrich has prided himself on a nontraditional campaign, but his advantages in the polls could shift if the only exposure to Gingrich comes through rivals' negative ads. Paul last week released an ad accusing Gingrich of "serial hypocrisy" and Bachmann opened her bus tour on Friday suggesting that he was arrogant during this week's final debate before the caucuses.

"I thought that it was outrageous and insulting, the way that he seemed to treat me like I was a student, and I'm not," she told CNN. "I'm a serious candidate for president of the United States."

Romney, a former Massachusetts governor who has kept Iowa at arm's length after investing heavily here four years ago only to come up short, planned town hall-style meetings in Charleston, S.C., and Myrtle Beach, S.C. Even so, his advisers note they have kept in touch with supporters of his 2008 campaign that came in second place in Iowa.

Meanwhile, both Bachmann's and Perry's bus tours continued to roll along, often visiting the same places days apart. Both are hoping to remind caucusgoers why they liked them during the summer. Each enjoyed a meteoric rise — followed by a precipitous fall.

And Santorum, who earlier this year completed his own bus tour of Iowa's 99 counties, continued to press forward with his deeply conservative message. Although he badly trails in the polls, he is hoping his work courting Christian conservatives pays off the way it did four years ago for former Arkansas Gov. Mike Huckabee.

Former Utah Gov. Jon Huntsman, who early on decided against competing in Iowa, planned a town hall-style meeting in New Hampshire. Huntsman, who also served as President Barack Obama's ambassador to China, has kept his focus on New Hampshire, where independent voters are the largest bloc and can vote in either party's primary.