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Analysis

If a thank-you note arrives in Newt Gingrich's mailbox in McLean, Virginia, the former House Speaker shouldn't be surprised if it's from Mitt Romney: the likely Republican presidential nominee may have Gingrich to thank for his frontrunner status.

In a surprising development, given Gingrich's intense dislike of Romney, Gingrich has been indirectly responsible for some of Romney's recent successes in the GOP primary. If Gingrich had dropped out of the race, say, after his resounding defeat in Florida in January, the dynamic of the Republican contest could be drastically different today.

In the month since Florida's primary, Santorum has suffered narrow defeats to Romney in Ohio and Michigan, defeats which have made it all but impossible for him to win the nomination - and defeats which might have been victories had it not been for Gingrich's continued presence in the race. On Tuesday in Ohio, for instance, Santorum apparently lost to Romney by only about 10,000 votes, a mere 0.8 percent margin of defeat. 175,000 voters, however, backed Gingrich that day and, polling shows, if he had not been on the ballot, Santorum would have benefited more than Romney and would have had a better chance of winning.

Sixty-three percent of voters in the Ohio Republican primary - the largest amount for any candidate - said the would be satisfied if Santorum were the party's nominee. Fewer - 57 percent - said they would be satisfied with Romney. Fewer than half - 48 percent - said they would be satisfied with Gingrich.

Romney may also benefited from Gingrich's presence in other states such as Alaska and Georgia. In Alaska, Romney squeaked out a win over Santorum by a little more than 400 votes. In that race, more than 1,800 voters, including Sarah Palin, backed Gingrich. In Georgia, meanwhile, Gingrich's home state, the former House Speaker cruised to an easy victory with 47 percent of the vote, trailed by Romney with 25 percent and Santorum with 19 percent. 39 percent of Gingrich supporters said Santorum's policy positions were "about right." Only 23 percent of Gingrich supporters said the same about Mitt Romney.

Give Santorum victories in Ohio, Alaska and Georgia and suddenly the GOP race looks a little bit different. While Romney would still be ahead in the delegate count - and still the favorite to eventually secure the nomination - Santorum would stand a much better chance at mounting a serious challenge for the party's nod, especially with the former Pennsylvania senator favored to win a slew of the upcoming primary states, such as Alabama, Mississippi, Kansas and Missouri.

That fact is not lost on Santorum's campaign, which has vociferously called on Gingrich to leave the race. As Super Tuesday wound down, Santorum's national communications director Hogan Gidley said a head-to-head matchup with Santorum was Romney's "worst nightmare", but that the continued presence of Gingrich and Ron Paul was preventing that from occurring.

"Look at the numbers… we'd be winning these states by ten points," Gidley said. "You're talking about the anti-Romney vote being split three ways."

The next morning Santorum's Super PAC - the Red, White and Blue Fund - followed suit, calling on Gingrich to abandon the race so that "conservatives would be able to make a choice between a consistent conservative in Rick Santorum or Mitt Romney."

"With Gingrich out of the race, Santorum would have won both Ohio and Michigan," Stuart Roy, an RWB Fund adviser, said. "Newt has become a hindrance to a conservative alternative."

The former director of Gingrich's South Carolina campaign even added her voice to the growing number of calls for Gingrich to get out now, although DeLinda Ridings wants Gingrich to exit not to give Santorum a better chance, but so Republicans can coalesce around Romney.

Despite Roy's claim, it is unclear if in fact Santorum would have been able to win Romney's home state of Michigan if Gingrich had not been in the race. Romney defeated Santorum there by a little more than 32,000 votes. Gingrich that day earned around 65,000 votes. That means Santorum would have had to win a huge percentage of those Gingrich votes - better than a 2-to-1 margin.

According to the New York Times' Nate Silver, Gingrich's absence would not have been enough for Santorum to triumph in the state.

"He would not have won Michigan - Mr. Gingrich received very few votes there so there was little marginal benefit to Mr. Santorum - although it would have flipped one Congressional district and therefore given him the majority of delegates in the state," Silver wrote on his Five Thirty Eight blog on the New York Times' website.

Overall, Silver wrote, if Gingrich had exited the race before South Carolina's primary in January - which he won - Santorum would have emerged victorious in four states that he lost: South Carolina, Georgia, Alaska and Ohio. But Romney would still be leading where it matters, in delegates.

"Mr. Romney would still be significantly ahead in the delegate count," Silver said. "I have him with 404 delegates versus 264 for Mr. Santorum and 71 for Mr. Paul. Mr. Romney's delegate total, in fact, is very slightly higher than it would have been before the redistribution of the vote. There are cases when the shift in votes costs him delegates, such as in winner-take-all districts, or when one of his opponents gains more votes and crosses a threshold that enables him to receive proportional delegates. But Mr. Romney is being given some votes under these assumptions - if not, as many as Mr. Santorum - and that helps in cases where the delegate allocation is more proportional. These factors came close to balancing out, but Mr. Romney gained about 10 delegates on net."

"Mr. Santorum, however, made the larger gains, winning about 110 delegates than he has taken in the real world with Mr. Gingrich on the ballot," he concluded.

On Wednesday Santorum acknowledged that he "wanted" Gingrich out of the race, but stopped short of calling on his opponent to step aside.

"I'm not saying I don't want him to get out. If he wants to get out, I'm all for him getting out. I'm for Mitt Romney getting out. I wish President Obama would just hand me the thing, but that's not going to happen," Santorum said in Lenexa, Kansas.

Gingrich, though, has said he isn't going anywhere… except on to campaign stops in upcoming primary states like Alabama and Mississippi, states his campaign calls must-wins.

"We're staying in this race because I believe it's going to be impossible for a moderate to win the general election," Gingrich said Wednesday in Montgomery, Alabama.

Earlier in the day, Gingrich said on "The Bill Bennett Show" that he might drop out if he thought Santorum could knock out Romney and Obama.

"If I thought he was a slam dunk to beat Romney and to beat Obama, I would really consider getting out," Gingrich said. "I don't."

Considering Gingrich has waged a bitter primary battle with Romney, depicting the former Massachusetts governor as a lying, hypocritical moderate, it is a little surprising that he now intends to stay in the race even if that benefits Romney.

On January 26 in Florida, as Romney launched an astounding barrage of attack ads against Gingrich - Romney and his allies spent over $15 million on ads in the state and all but one of those ads was negative. Gingrich has since then ripped into Romney, denouncing his campaign, his background, and his character.

"To have his campaign take on a lifetime of work and lie about it, frankly I do find infuriating," Gingrich railed. "I think it is one of the most dishonest things I've seen in politics. It is so fundamentally abusive."

"Here's a guy a who owns Freddie Mac and Fannie Mae stock. He owns a Goldman Sachs subsidiary that forecloses on Floridians. He is surrounded by lobbyists who are paid by Fannie Mae and Freddie Mac to stop reform. And on that front he decides to lie about my career? There's something about that hypocrisy that should make every Americas angry."

"I am angry," he continued. "But I think I'm angry and every American should be angry. How can somebody run a campaign this dishonest and think he's going to have any credibility running for president?"

Only four days later, in an interview with ABC News in Tampa, Gingrich continued to denounce Romney, saying he has "a profound character problem."

"He governed as a liberal who was pro-abortion, pro-gun rights, pro-tax increases, and pro-gay rights. Appointed liberal judges. Passed Romneycare," Gingrich said.

But now this is the same rival who Gingrich is indirectly helping by staying in a race that has left him beaten, bruised, and with virtually no shot at all of winning the nomination. He has only won two states - South Carolina and Georgia - compared to six for Santorum, not counting Missouri, which last month held a primary - won by Santorum - but it was known at the time that the primary would not affect the state's delegate allocation in favor of caucuses in March.

Ultimately, playing the game of "what might have been?" is a pointless exercise. Gingrich didn't drop out after his loss in Florida. Santorum didn't win Ohio, Georgia, and Alaska. And Romney now has a huge - seemingly insurmountable - lead in the Republican race, with 401 delegates compared to 177 for Santorum.

The only thing left is for Romney to secure the 1,144 needed to lock up the nomination… and perhaps send that thank-you note to Gingrich.

Matthew Jaffe is covering the 2012 campaign for ABC News and Univision.