Mitt Romney won six states and a sizable number of delegates on the biggest election night of the Republican primary season.

The GOP frontrunner and Rick Santorum were locked in a dead heat for several hours into the night before the Associated Press called the race for Romney at around 12:30 a.m. EST.

Ohio – Super Tuesday’s most coveted prize in terms of political importance – had been widely regarded as a test of Santorum’s ability to compete with Romney in a traditional fall battleground.

Romney also took Massachusetts, Virginia, Vermont, Idaho and Alaska.

“I’m not gonna let you down,” Romney told a Boston crowd just before congratulating his opponents. “I’m gonna get this nomination. We’re going to take your vote, a huge vote in Massachusetts, and take that all the way to the White House.”

He added, “You have not failed. You have a president that has failed you, and that’s going to change. … This president has run out of ideas. He’s run out of excuses, and in 2012 we’re going to run him out of the White House.

In Steubenville, Ohio, Santorum told supporters, “This campaign is about the towns that have been left behind and the families that have made those towns the greatest towns across the country. We have won in the West, the Midwest and the South, and we’re ready to win across this country.”

In closing, he said, “Against the odds, we keep coming back. We are in this thing, not because I so badly want to be the most powerful man in this country. It’s because I want so badly to return the power to you in this country.”

Santorum won Tennessee, North Dakota and Oklahoma, where Newt Gingrich had hoped to prevail.

Gingrich captured Georgia – the  state with the largest number of delegates at stake on Super Tuesday. With 95 percent of precincts reporting, he won 47 percent of the vote. Romney came in second at 26 percent, Santorum at 20 percent and Paul at 6 percent.

He declared to a crowd, “The national elites, especially the Republican Party, had decided that a Gingrich presidency was so frightening, they had to kill it. But you wouldn’t let them do it.”

Referring to all the other candidates who were “supposed to” crowd Gingrich out, including Tim Pawlenty, Michele Bachmann, Rick Perry, Herman Cain and Santorum, Gingrich said, “There are lots of bunny rabbits that run through. I’m the tortoise. I just take one step at a time.”

While Romney had bombarded Ohio’s airwaves with campaign ads, Santorum’s message was favored by the state’s evangelicals and blue-collar workers, and he is familiar in the eastern part of the state from his time as a representative and senator in nearby Pennsylvania. However, Santorum was ineligible for 18 of the state’s 66 delegates due to filing issues.

Gingrich’s win in Georgia, a state he represented in Congress for 20 years, may be his final opportunity at a comeback in the race for the GOP nomination. In recent weeks, he has battled to keep his presidential candidacy alive and staked its future on a Georgia win. Romney’s super PAC spent about $1.5 million in the state in an attempt to prevent Gingrich from obtaining 50 percent of the vote. Georgia is a proportional state with 76 delegates.

As most expected, Romney won Vermont and Virginia – both hybrid proportional states with 17 and 49 delegates, respectively. Santorum and Gingrich failed to qualify for the Virginia primary ballot, so Romney shared the ballot with only Ron Paul. According to Virginia exit polls conducted for the Associated Press, one in three voters reported that they would have supported a different candidate if Gingrich and Santorum had been on the state’s ballot.

Meanwhile, Ron Paul told his supporters in Fargo, N.D.:

“If you look at the candidates today, there is very little difference, except for one. The rest of the candidates support the status quo. … Foreign policies never change, monetary policy doesn’t change, there’s no challenge to the Federal Reserve system, and most of all, there’s no desire to protect personal liberty, personal privacy, protect us from the intrusiveness of the federal government, to protect your right to use the Internet. These are the kind of things that are so important to so many people and, unfortunately, that is not offered.”

Nearly one-third of the 1,144 delegates needed to clinch the nomination were at stake on Super Tuesday, with primaries in Ohio, Georgia, Massachusetts, Vermont, Virginia, Oklahoma and Tennessee and caucuses in Idaho, North Dakota and Alaska.

All of the Super Tuesday states allocate delegates proportionally or hybrid proportionally. For an in-depth description of how delegates are allocated for each state, see the Washington Post’s detailed analysis on the subject.

According to the Associated Press’ exit poll of GOP primary voters in Ohio, Republicans are overwhelmingly distressed with the federal government and profoundly apprehensive about the direction of the national economy. Nine in 10 Ohio Republicans said they are currently dissatisfied with the federal government, and almost every voter polled was worried about the nation’s economic future.

The AP polled GOP voters in seven of the 10 Super Tuesday states. Republicans in all seven states said the economy is the most concerning issue this election.

The polls also indicated that seven in 10 Tennessee GOP voters are reportedly born-again or evangelical Christians. On the other hand, less than one in five Massachusetts voters reported similar religious beliefs.

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