12:30AM EST: Mitt Romney has won the Ohio primary, the AP projects.

11:31PM EST: All eyes were on Ohio as Mitt Romney took four states and Rick Santorum three on Super Tuesday. But the rivals were so close in the critical Buckeye State that NBC News has indicated that the cliffhanger could go on through the night. With 86 percent of the vote in, Romney and Santorum were neck-and-neck. The state, depending on the outcome, could propel Romney to the nomination or renew doubts about his ability to take on President Obama in November. The projections showed Romney took his home state of Massachusetts, Virginia, Vermont and Idaho; a newly resurgent Santorum won Tennessee, Oklahoma and North Dakota, while Georgia went to Newt Gingrich. More than a third of the 1,144 delegates required to clinch the nomination are at stake Tuesday.

11:25PM EST: Mitt Romney has won the Idaho primary.

10:15PM EST: Rick Santorum won the North Dakota caucuses on Super Tuesday.

North Dakota didn’t receive as much attention as other nine Super Tuesday states. Mitt Romney and Santorum visited the state once, according to the Associated Press.

Ron Paul, on the other hand, visited multiple times and seemed like a good fit for the libertarian Republican: the state leans heavily toward independents. Paul, who drew large crowds of Tea Partiers there, decided to spend the evening of Super Tuesday in North Dakota.

The state has a total of 28 delegates which are awarded at a state convention on a proportional system.

8:50PM EST: Rick Santorum won the Oklahoma primary on Tuesday night.

It will likely be an incomplete victory for the former Pennsylvania senator: Had he taken 50 percent of the popular vote, he would have been awarded all of the state’s 43 delegates, which instead will be allocated proportionately.

Oklahoma is a socially conservative state with a large evangelical Christian population, which matches up with Santorum’s base of support.

Santorum has called Oklahoma “ground zero for the conservative movement” and campaigned in the Sooner State as late as Sunday.

8:39PM EST: Rick Santorum came out on top in Tennessee on Tuesday, defeating Mitt Romney and his other GOP rivals in the conservative, southern state.

Santorum’s win was an important symbolic victory for the former Pennsylvania senator, who has worked diligently to position himself as the most conservative candidate in the race.

Fifty-eight delegates were at stake in the contest. Of those, 28 will be awarded proportionally based on the statewide vote, because no candidate broke through the 66 percent threshold to win them all. Another 27 delegates will be awarded by congressional district, in addition to three unbound national party delegates.

8:06PM EST: Mitt Romney won a clear victory in his home state of Massachusetts on Super Tuesday.

Multiple networks called Massachusetts for Romney as the time polls closed at 8 p.m. ET.

Romney did not have to sweat his primary win in Massachusetts, the state where he lives and served as governor. The most recent polling, released Feb. 17 by Suffolk University, showed him leading by almost 50 points over Santorum.

Romney won 51 percent of the Massachusetts vote in 2008, and the other GOP candidates this cycle did not expend much energy in the state. Consequently, Romney spent very little time in Massachusetts himself.

Massachusetts awards 41 delegates using a proportional system, so the question most observers were asking on the eve of the vote was how many Romney could win. Candidates are required to win at least 15 percent on a district-by-district basis in order to be awarded delegates, and Massachusetts Republican Party Chairman Bob McGinn was pushing for a big win for Romney that he hoped would turn the traditionally Democratic state into a swing state for the general election.

7:41PM EST:Mitt Romney won the Vermont primary on Super Tuesday.

The victory was an easy one for Romney given the state’s large population of moderates and proximity to Romney’s home state of Massachusetts.

Vermont will award a total of 17 delegates at the Republican National Convention.

7:20PM EST: Mitt Romney will win the Virginia primary, beating Ron Paul the only other candidate on the ballot.

Virginia’s polls closed at 7 p.m. and, the television news networks called the race for Romney a short time later. Romney’s lead in the state had steadily grown in the latest polls, and he was up by 43 points in the most recent NBC News/Marist poll of voters taken at the beginning of the month.

7:03PM EST: Newt Gingrich has won the Republican presidential primary in his home state of Georgia.

Mitt Romney is ahead in Virginia and Vermont as voters across 10 states choose a GOP candidate for president in the Super Tuesday balloting. Romney and Rick Santorum are waging a fierce fight to win Ohio.