Mitt Romney won strong support Tuesday from Republicans seeking a candidate who can topple President Obama in November's elections, according to an entrance poll of GOP voters attending Iowa's presidential caucuses.

Rick Santorum countered with solid backing from Tea Party supporters, religious voters and other conservatives. And Ron Paul scored highly with young voters, independents and people concerned about huge federal budget deficits.

The divisions helped explain a night in which Romney and Santorum ran neck and neck with Paul a close third -- and ahead of their three other competitors.

Given a choice of four qualities they wanted in their party's nominee, about 3 in 10 said they wanted someone who could defeat Obama this fall. Forty-nine percent of that group said they were backing Romney.

Santorum, whose candidacy surged in recent days while emphasizing family and faith, led among those seeking a candidate with strong moral character, with 39 percent picking him. Santorum and Paul, a libertarian, were running about evenly among those who said they wanted a true conservative as their standard bearer.

Nearly 3 in 10 supporters of the Tea Party movement were supporting Santorum, and about the same proportion of born-again or evangelical voters were also backing him.

Paul had the backing of 48 percent of voters under age 30 and nearly as many independents, giving him large leads in both categories.

HOW IOWA GOT ALL THE ATTENTION

Since the 1840s, political activists in Iowa have gathered on dark winter nights to take care of party business. Only for the past 40 years has anyone outside the state taken notice of these Iowa caucuses.

Everything changed in 1972, when Democrats moved their meeting to January, making Iowa's presidential preference vote the first in the nation.

Noticing the change, candidate George McGovern gave Iowa extra attention, then finished a surprising second and went on to win his party's nomination.

Iowa Republicans moved up their caucus in 1976, and candidates have paid rabid attention to Iowa ever since.

THE CANDIDATES' FINAL APPEALS

Mitt Romney: Democrats will "poison the American spirit by pitting one American against another and engaging in class warfare. I believe in an America that is one nation under God, and I will keep it that way."

Ron Paul: "I defend the Constitution."

Rick Santorum: "This is an important moment for our country."

Newt Gingrich: "All of you have been drowning in negative attack ads. None of them have come from me. Iowans have an opportunity tonight to send a message to Washington and to the political system that the age of negative consultants and negative attack ads is over."

Rick Perry: "This is Concord. This is Omaha Beach. This is going up the hill, realizing that the battle is worthy. This is about sacrifice. Every man and woman has sacrificed your time, your treasure, your reputation. But you're doing it out of love for this country. That is what gets us up every day, gives us the courage, the fortitude, the focus to go do what we have done for the last almost six months."

Michele Bachmann: "We're moving on. We're moving forward because this election is far from over. This is the opening chapter. Tonight is the first vote. We've got a long road to go."

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