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Mitt Romney walked away the Super Tuesday winner, after building his delegate lead with victories in six states and pulling off the headline-grabber of the night -- Ohio.

The former Massachusetts governor narrowly edged out Rick Santorum to take the Buckeye State, a vital general election battleground which was considered the Super Tuesday prize both for its delegates and bragging rights.

Santorum, though, claimed victories in three states. Newt Gingrich won one state, his home of state of Georgia, by a double-digit margin. Ron Paul did not win any of the contests.

Far from a decisive election night, the Super Tuesday results ensure the protracted and unpredictable GOP primary contest will press onward, as the candidates head next into a set of southern, western and midwestern states.

In Ohio, Romney was projected the winner shortly after midnight. With nearly all precincts reporting, Romney won with 38 percent to Santorum's 37 percent -- barring any unforeseen vote correction by Ohio officials. It was a major win for Romney in a state where he trailed Santorum just days ago.

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    Romney also won contests in Alaska, Idaho, Vermont, Virginia and Massachusetts, the state where he served as governor. Virginia was perhaps the least suspenseful contest of the night, as only he and Paul qualified for the ballot.

    At his post-election rally in Boston, Romney kept his focus trained on President Obama and expressed confidence in the momentum of his delegate-amassing operation. His victories Tuesday night will help him build his delegate lead substantially.

    "I'm not going to let you down. I'm going to get this nomination," Romney assured the crowd. Romney was also expected to benefit from the fact that in Ohio, filing problems left Santorum ineligible for 18 of the state's 66 delegates.

    Santorum nevertheless notched important victories in North Dakota, Tennessee and Oklahoma. The wins help Santorum regain his footing after losing out to Romney in Michigan and Arizona a week ago, and in Washington state over the weekend.

    Santorum, striving to be seen as the lone conservative alternative to Romney, sounded a confident tone as he addressed supporters in Steubenville, Ohio.

    "We can add to Iowa, Missouri, Minnesota, Colorado -- now Oklahoma and Tennessee," Santorum said, ticking off his primary and caucus victories to date. "We have won in the West, the Midwest and the South, and we're ready to win across this country."

    As he has before, Santorum said he's the only Republican candidate who can go toe-to-toe with Obama on "the most important issue of the day" -- the federal health care overhaul.

    "I've never been for an individual mandate, at a state or federal level," Santorum said, in an implicit jab at the past support by Gingrich and Romney for an individual requirement to buy health insurance.

    Gingrich won the night's most valuable contest in terms of sheer delegates. His victory in Georgia was also his first since the South Carolina contest in January.

    The former speaker rallied a crowd of supporters in Atlanta Tuesday night, as he lambasted the media and the "elite" for trying to "kill" his campaign earlier in the season. "I hope the analysts in Washington and New York who spent June and July explaining our campaign was dead will watch this tonight and learn a little bit from this crowd and from this place," he said.

    Gingrich used a lengthy speech to decry Obama's energy policy and promote his own campaign promise to bring gas prices down to $2.50 a gallon. Making clear his campaign will go on, he claimed he is the only GOP candidate in the field who can debate Obama "decisively" going into November.

    "I'm the tortoise. I just take one step at a time," he said.

    Gingrich's victory in Georgia, which he represented in Congress for 20 years, gives the former House speaker a much-needed boost after a rough six weeks on the campaign trail. Since winning South Carolina, Gingrich's most frequent primary finish has been fourth place, though he had a handful of second- and third-place finishes. With two wins now under his belt, both in the South, Gingrich can head into next week's contests in Alabama and Mississippi making the argument that he is the candidate favored by voters in the deep South.

    Gingrich is expected to pick up the majority of the 76 delegates in Georgia.

    Despite the split decisions, exit polling on Tuesday showed voters were fairly united on one point -- the desire to beat Obama. The polling, practically across the board, showed beating Obama is the top goal of Republican voters in seven states -- where exit polling data on Tuesday's presidential primaries also showed the economy is the top issue.

    The seven states voting in primaries Tuesday represented a wide range of Republicans, from the most moderate in Vermont and Massachusetts to the most conservative and religious in Oklahoma and Tennessee.

    In total, 419 delegates were at stake on Super Tuesday, more than the total number that have been awarded in all the contests to date.

    Paul was the only candidate to visit Alaska, with its strong libertarian streak, and also worked North Dakota, where Democrats and independents can vote.

    At an early rally in Fargo, N.D., Paul made an effort to distinguish himself from the rest of the field -- claiming the rest of the candidates are drawing from the same playbook when it comes to foreign policy and monetary policy.

    "If you look at the candidates today, there is very little difference except for one," Paul said. "The rest of the candidates support the status quo."

    Paul was projected to pick up a few delegates in Virginia, though Romney gained the overwhelming majority. Paul may have gotten an assist from groups supporting Gingrich, who were urging voters to limit the amount of delegates awarded to Romney.

    Gingrich, who lives in Virginia, was not on the ballot there and could not even plug in a vote for himself, as the state does not allow write-ins.

    But while Gingrich couldn't participate in Virginia, his southern strategy had been fully focused on Georgia. Sue Everhart, the Georgia Republican Party chairwoman, said before returns came in that a strong performance in Georgia, coupled with a strong performance in subsequent southern contests, would give him "the steam to push him all the way to Tampa, Florida."

    Gingrich has been left for dead politically at least twice before in this primary contest. Yet splitting the so-called conservative vote may just redound to Romney, who would see that wing of the party split between Gingrich and Santorum, giving the former Massachusetts governor the chance to run up the middle.

    Going into Super Tuesday, Romney led with 203 delegates. Santorum was in second with 92, followed by Gingrich with 33. Paul had 25. It takes 1,144 to win the nomination.