AMES, Iowa—Mitt Romney may have some help in Iowa: Ron Paul.

The Texas congressman's allies and others say that he drains support from the rising Newt Gingrich, and, if that turns out to be the case during the Jan. 3 caucuses and Paul manages to triumph here, the theory is that Romney would benefit in the long-run.

"If Ron Paul can chip away at Gingrich just enough, he could conceivably win the caucuses, but he doesn't have the longevity of Gingrich" because Paul has trouble expanding his support beyond his libertarian-leaning base, said Tim Albrecht, an Iowa operative who worked for Romney during his failed presidential bid four years ago.

The theory among some Republicans is that even if Paul, who has been working this year to shed his 2008 image as a GOP gadfly, earns credibility as a mainstream candidate by winning the Iowa caucuses this time, he'd struggle to challenge Romney in New Hampshire, South Carolina and Florida the way Gingrich could because polls suggest he doesn't draw enough support from across the Republican ideological spectrum.

Whether that assumption is correct or not, a Paul victory in Iowa over Romney still would be a set-back for the former Massachusetts governor who for much of the year has been seen as the most likely Republican to win the GOP nomination.

The question is: to what degree?

Some Republicans say a victory by Paul -- who many Republican operatives doubt can win the race -- could help curb the perception of a crushing loss for Romney, who has tried to tamp down expectations that he'll do well here even as aides operate an under-the-radar Iowa campaign and TV ads intended to help him are starting to flood the Iowa airwaves.

A recent Des Moines Register poll this month showed Paul in second place behind Gingrich, with 18 percent support. That's up from 12 percent in October and 7 percent in June.

"The reality," said Steve Schmidt, who ran Sen. John McCain's campaign in 2008, "is that candidates who are not going to win the nomination play a very important role in determining who does."

Paul, to be sure, is a factor in the race.

He raised $5 million between July and September, and supporters say Paul will be able to stay in the contest as long as he wants because of a loyal following that sends him cash when he asks and new GOP rules that award convention delegates proportionally. And he's not being shy about trying to bloody his rivals -- particularly Romney's chief challenger. This week, Paul's on the air with a blistering commercial hitting Gingrich for "serial hypocrisy."

To back up their assertion that Paul draws support from Gingrich, Paul's allies point to data that show very little overlap between their candidate's supporters and Romney's backers. They argue that because very few Romney backers would pick Paul as their second choice, it likely won't help Paul to go after Romney. But, they say, attacking Gingrich has little downside because voters who flee Gingrich are as likely to pick Paul as a second choice as they are to pick Romney.

Unlike four years ago, Paul is running a much more methodical campaign and, in Iowa at least, is seeking to win the state the old-fashioned way.

He has spent more than a month and half campaigning here, and more than half a million dollars on ads. His campaign is sending out mail and making phone calls. And his campaign has proven that it knows how to organize supporters, a necessity to turn out people to vote at precinct caucuses on a cold January weeknight. He came within about 150 votes of beating Rep. Michele Bachmann at the key Iowa test vote in August -- but his near-victory was barely mentioned in the press, supporters complain.

A recent New York Times- CBS poll showed 70 percent of likely caucus-goers had heard from Paul's campaign in some way.

Paul's support is particularly strong among young people.

At least 1,000 students crowded into the Iowa State student union Thursday night to hear Paul's rambling, half-hour speech -- and then many waited nearly 45 minutes to have their photo taken with the congressman.

The better organized campaign is driven in part by the political operatives who helped Paul's son, Rand Paul, win his Senate seat in 2010. Allies say that victory helped teach Paul's ideological backers how to turn grassroots, movement support into a winning campaign.

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