The NBC News Elections Desk reports that in the Michigan primary, with 30 delegates at stake, Rick Santorum and Mitt Romney will split that state's delegates 15 apiece.

Michigan allocated its delegates winner-take-all by congressional district.

The Romney campaign says the former Massachusetts governor now owns two shotguns purchased in the past five years, since he last ran for president.

Earlier today, per NBC's Garrett Haake, a questioner asked what the candidate would do to protect gun rights (and allow people to protect their families from a tyrannical government). 

"I believe in the second amendment," Mitt Romney said. "I’ll protect the second amendment. I have guns myself. Not going to tell you where they are. Don’t have them on myself either, alright."

This raised the question of whether Romney purchased a weapon in the past five years or if he was retelling a tale from his last run for president.

In January 2007, Romney said, per the Boston Globe: "I have a gun of my own. I go hunting myself. I'm a member of the NRA and believe firmly in the right to bear arms."

It turned out, however, that he didn't actually own the gun he was referring to; it was his son Josh's.

"Asked by reporters at the gun show Friday whether he personally owned the gun, Romney said he did not," the Globe wrote. "He said one of his sons, Josh, keeps two guns at the family vacation home in Utah, and he uses them 'from time to time.' The guns are a Winchester hunting rifle and a Glock 9mm handgun, which Romney uses for target shooting. Romney also described himself as a sportsman who learned to shoot as a boy rabbit hunting in Idaho with a .22 rifle. He fondly recalled shooting quail last year at a Republican Governors Association event in Georgia.

" 'I ... had a good time and actually knocked down a couple of birds,' he said."

Romney, who no longer owns that vacation home, also recalled: "As a boy, I worked on a ranch in Idaho and shot rabbits with a single shot .22 rifle. After a while my cousin said 'you're not very good at that. Try using this semiautomatic.'"

Romney, in trying to appeal to conservatives, had a tough time the last time he ran proving his gun-toting bona fides.

His quotes were circulated from his 1994 Senate race that he said he didn't "line up" with the NRA, and, famously described himself as a "rodent and rabbit hunter ... small varmints, if you will."

"I'm not a big-game hunter," Romney said. "I've made it very clear, I've always been a, if you will, rodent and rabbit hunter all right. Small, small varmints, if you will. And I began when I was, oh, 15 or so, and hunted those kinds of varmints since then. More than two times. I also hunted quail in Georgia, so I've-- it's not really big-game hunting, if you will. It's not deer and large animals. But I've hunted a number of times of various types of small rodents."

NBC News projects that Mitt Romney has won Michigan.

With 84% of the vote in at about 10:47 pm ET, Romney was up 41%-38% over Rick Santorum, narrowly escaping what could have been a crushing blow to his candidacy in the state where he grew up.

A quick look at religion in the exit polls:

- Mormons made up 14% of Arizona GOP primary voters; Mitt Romney, who is Mormon, won them with 91%. Those numbers are up slightly from 2008, when Mormons were 11% of total, and Romney got 88% of them).

- In Michigan, GOP primary voters who identified as Catholics (30% of the total) voted for Romney (43%-37%) over the staunch conservative Catholic, Rick Santorum.

- But Santorum won evangelicals/born-again Christians (42% of total) by a wide margin -- 50%-32% over Romney.

The GOP primary race in Michigan, Mitt Romney's home state, is "too close to call," NBC News projects.

Polls in the run up to Michigan have shown a tight race between Romney and Rick Santorum.

NBC News does project, however, Romney to be the winner in Arizona.

Since Arizona is winner-take-all, Romney will win all 29 of the state's delegates.

Interesting fact: Despite the -- warranted -- focus on Michigan over Arizona, Romney will actually win more delegates out of Arizona than Michigan, no matter the outcome, because Michigan is winner-take-all by congressional district.

GRAND RAPIDS, Mich. -- As Michigan and Arizona voters went to the polls today, the gloves came off between the two top contenders for the Republican presidential nomination.

The first blow came this morning in Livonia, Mich., when Mitt Romney called Rick Santorum "an economic light weight." The remark kicked off a day of verbal sparing and boxing metaphors between the two both stumping in the Wolverine State. "I don't think he understands the process of job creating," Romney added.

It was later that Santorum responded to the former Massachusetts governor, calling him "a lightweight on conservative accomplishments."

The latest candidate to surge in the polls attempted to spin Romney's comments as an attack on his wealth.

"I'm not a heavyweight," Santorum said. "I’m not a multimillionaire. I'm someone who has gone out and worked hard and learned my economics from shining shoes."

(Santorum may not be as wealthy as Romney or even Newt Gingrich, but the former Pennsylvania senator made more than $1 million in 2010 and half of 2011.)

Of the two states holding primaries today, it is Michigan that has received the bulk of attention. Santorum is threatening in the state where Romney spent his youth and his father served as governor. As a result, the contest here has gotten increasingly negative, with each candidate running scorching television ads in the state.

Romney is pointing to a robo-call from the Santorum campaign as the latest example of the mudslinging. The call features a message calling on Democrats to vote against Romney in the Tuesday primary.

Romney said on Fox News that the calls are "outrageous and disgusting, a terrible dirty trick at the last hour."

But Santorum and advisers contest the move was nothing more than an attempt to reach out to a broad base of voters. "I don't remember Mitt Romney running around and doing anything but trying to encourage Democrats and independents to vote for him in New Hampshire," Santorum contended.

A win for Santorum in the state would be a tremendous boast for a candidate still struggling to to keep compete with the money and organization of his chief rival. However, campaign advisers argue that the race is close enough that they don't need an actual Santorum win to claim a victory.

"I think it's already a win by the fact that it's this competitive with Mitt Romney in his home state," senior Santorum strategist John Brabender said on MSNBC.

Both candidates will take their campaigns to Super Tuesday states tomorrow, with Romney heading to Ohio and Santorum to Tennessee.

Mitt Romney is pretty upset about Rick Santorum robo-calling Democrats to try and get them out to vote for him. Romney called it "a real effort to kidnap our primary process."

This might be why. In 2000, John McCain won Michigan by 8 points, 51%-43%, over George W. Bush. And about 10 percent of the people who voted for McCain were Democrats.

About 1.3 million voted in the 2000 Michigan primary. Nearly one-in-five -- 17% -- voters told exit pollsters they were Democrats. (That would be about 75,104 people; 82 percent of them went for McCain, meaning 61,586 Democrats voted for McCain.)

McCain's total vote was 650,805, so the 62,000 or so is about 9.5%. (Of course, these aren't exact numbers because exit polls have a margin of error but they're pretty close.)

Only about half -- 48% -- of the 2000 Michigan primary voters identified as Republicans; 35% were independents.

Pro-Rick Santorum robo calls, using the National Rifle Association's name, are running in Michigan ahead of tomorrow's primary, an NRA member in Michigan emails First Read.

The call compares Santorum and Romney's NRA records, urges members to vote for Santorum, and uses Romney's own words against him.

But the NRA, which hasn't endorsed a candidate, says it's not running the calls.

"We're not doing anything," said Andrew Arulanandam, director of Public Affairs for NRA-ILA, or Institute for Legislative Action. "Our position is anyone would be better than Barack Obama. It's absolutely wrong. We are not paying for anything. We're not spending one cent. That is not us -- completely, unequivocally not us."

Arulanandam said there's no way a campaign or someone supporting a campaign, could have gotten their member list. But someone could get another list, like a hunting-license list, that could have some overlap.

The call tells members that if they care about their right to own a gun, then this message is critical. It notes that Santorum received an A-plus rating from the NRA and calls him a a friend of sportsmen and hunters. Romney, on the other hand, is derided as a disaster for gun owners and uses his own words against him.

"I don't line up with the NRA," Romney is heard saying, replaying his comments from his 1994 Senate bid.

Then, the ad urges Michigan residents not to vote for a moderate from Massachusetts and not to let him destroy gun rights and then plays the Romney quote again.

TROY, Mich. -- It may just turn out that Mitt Romney's most important endorsement in his battle against Rick Santorum for the Michigan primary isn't Gov. Rick Snyder, or any of the host of legislators or local luminaries who've backed his candidacy this cycle, but instead Santorum himself - who supported Romney in 2008.

Saturday, before more than a thousand attendees of a conservative conference, Romney used Santorum's 2008 endorsement as a pivot, around which he turned from explaining his own vision to throwing a verbal haymaker at Santorum, who earlier Saturday at the same event called for the party to nominate a "consistent conservative" to take on Barack Obama.

"I can attest to my conservative credentials by quoting someone who endorsed me in 2008 campaign. Senator Santorum was kind enough to say on the Laura Ingraham show, he said, Mitt Romney, this is the guy who is really conservative and who we can trust. And when he came out and endorsed me he said these words: He said he is the clear, conservative candidate." Romney said. "He's right, I'm the conservative candidate and what we need in the White House is principled, conservative leadership and I¹ll bring it."

The audience reacted audibly here at the Americans For Prosperity conference as Romney proceeded to dissect Santorum as a creature of Washington who had sold out his principles.

"In that last debate we heard something about business as usual in Washington," Romney said. "When the senator mentioned that sometime you have to take one for the team what he was describing was the circumstances where he disagreed with something on principle but he had to vote for it because that was taking one for the team. We can't do that anymore. We can't continue to take one for the team. My team is the people of the United States of America, and I'm going to fight for that team, not for the partisans in Washington.

As the race for Michigan has tightened to a margin-of-error contest, Romney has racheted up his tactics and his rhetoric against Santorum. Saturday he delivered his most complete rebuke of the former senator's record, folding in attacks old and new, and hitting Santorum for supporting Planned Parenthood funding and Title X -- even though he claimed to be against those programs, and for funneling cash into earmark projects like the so-called "Bridge to Nowhere."

The newest line in the attack came in the form of tying Santorum to his former Senate colleague Arlen Specter, whom Santorum endorsed over conservative challenger Pat Toomey in 2004, and during Specter's run for president in 1996.

"Remember how he described how he supported Arlen Specter as an effort to get a deal to get some judges approved and then Arlen Specter said there was no such deal and he backed away from that," Romney said. "It was also 1996 when he supported Arlen Specter, by the way ... when Arlen Specter was running for president. Arlen Specter, the only pro-choice candidate we've seen in that race, there were other conservatives running like Bob Dole, he didn't support them. He supported the pro-choice candidate, Arlen Specter. This taking one for the team...  that's business as usual in Washington."

Romney's address here was well-received, including at least one standing ovation, but could be a preview of a more negative race to come between Romney and Santorum. Asked after his remarks why he had taken a more aggressive approach today against Romney, Santorum told reporters he had to "fight fire with fire."