Some think the South is Santorum's heartland right now, and to some extent (sadly, in my opinion) it is. In spite of that, when you look at the trends, the real story with respect to the South's differences has little to do with Santorum, and more to do with Mitt & Newt. Daniel Elazar posited that the American Political Tradition is actually made up of 3 distinct political traditions, present and mixing in different proportions in different parts of the country. Without going into too much detail, these are the Moralistic, Individualistic, and Traditionalistic, and most of Dixie is Traditionalistic (TX & FL are hybrid).
The very reason I decided I'm done with Newt - his class-warfare rhetoric - probably explains why he has sunk in the Midwest and is still competitive in down South. Traditionalistic cultures don't mind wealth, but economic and political power tends to be legitimized by a structure with paternalistic social and religious overtones. So, when Newt pops Mitt as a "vulture capitalist", and says capital gains are fine when they "create jobs", he may strike many of us (I know its true for me) as playing the same class-warfare fiddle that Obama's "fair share" strums; however, it probably taps into the traditionalistic cord.
Plus, notice a vote trend difference between the South and states where Mitt is winning. Take Florida (again, Elazar said in the '60s/'70s Florida was hybrid, and immigration has only exacerbated this trend). Polling showed that Ron Paul competed with Mitt Romney for voters, while Newt & Santorum largely competed for the same pool. You can call this a "not-Romney" pool, a neo-conservative wing, a less educated & affluent rump, or whatever other moniker sounds descriptive, but the name is irrelevant. From a political science perspective, what is relevant is that two distinct voting pools largely (not wholly) were apparent, each with a critical mass to be competitive.
Compare this to the South: In either Mississippi or Alabama (or both, but I think one or the other), Mitt didn't come in 2nd, he instead took the Bronze, with Newt taking silver in Santorum's shadow. Now, if those two voting pools were composed similarly and similarly proportioned with respect to the population in the rest of Dixie as in Florida, and Newt & Santorum both came from Pool A, you'd expect to see one and only one of those two individuals in the final two along with Romney. The competition between the intra-GOP pools would be for Gold & Silver, while the competition between Newt & Santorum would largely be between 2nd/3rd or 1st & 3rd, but not 1st & 2nd.
I would submit there are three reasons for the anachronism. First, Mitt doesn't have the Establishment-Electable mantle in Traditionalistic areas. This has less to do with polls that the idea of "electability" might imply. Political Scientists spend so much time focused on empirics, they sometimes forget to backup and reassess whether a concept has changed, or one layer of one with multiple dimensions has changed. Electability has not merely to to do with one's polling, but also one's social standing and legitimation by the political system. Is this gentleman (or lady, had Michele Bachmann prevailed) an insider, or an "other"? Regardless of the answer, one can poll well or poorly depending on the climate.
National polls would seem to establish a unified climate, but it's more appropriate to say they establish unified odds. Even that is a stretch, since two candidates can take different Electoral College strategies to victories, but we can lay that consideration aside for a moment. Dixie has a different climate for Mitt (and Ron Paul, but for different reasons). That traditionalistic power structure does not give him the same social standing as, say, an Individualistic State. "Success" in the marketplace and credentials from the Ivy League have relatively less - do not read "no" or even "little" in absolute terms - cachet in the Traditionalistic areas, that encourage a pre-capitalist mindset.
Notice in St. Charles County, Missouri, the party actively supported Rick Santorum in the caucus after he won handily in the non-binding primary. I would argue that even though Santorum likes to try to play the challenger-outsider role, and is from Pennsylvania (Individualistic), he has just as much claim to being the Establishment candidate in Louisiana today, because he has framed his candidacy in Traditionalistic terms. So the one advantage to Santorum may be legitimation, but in Deep South, Newt has a toe-hold on that. In fact, Mitt would have done better for himself if he would have embellished his trade bellicosity toward China down South, where he could tap into commercial antagonism without going the moralistic, Democratic, class-warfare route.
The other two reasons are more straight forward, and center around religiosity. I don't think you can take the stronger religious role out of the equation. Many have asked why for all Mitt's policy flexibility, he won't just atone for RomneyCare. I'm a strong opponent of ObamaCare, and I do think the top-down policy stance of health care reform in Massachusetts makes Mitt's credibility on repeal shaky; however, I don't think Mitt believes he needs to atone for anything. He's said there are some things he likes about it, and some things he would "do differently", which he probably sees as admitting the classic "mistakes were made". An error and a lapse in judgment are two different things. To see how relevant this is, lets turn back to Newt.
Many might be surprised that the region where Newt's candidacy is still on life support is in one of the most evangelical, in light of him being the only GOP contender with three marriages and an adulterous past. Recall, though, how he handled that: By immediately admitted he done wrong, and he has changed. Yes - here is where culture, not just economics, matters. Mitt tries to paper over his changes, drawing lines of continuity to show it's a growth, maturation, or evolution of thought. Newt - the historian - paints his political path in terms of epochs, embracing the discontinuity. (Ironically, the latter method is simultaneously pre-modern and postmodern, though the postmodern appreciates the discontinuities may be part of a larger continuum.) The South wants you to fall on your sword, and admit you are fallen, then draw from those ashes your new armor.
Similarly, the polish that makes Mitt seem ready for prime time probably hurts Mitt down South. Wealth is sometimes a trapping for which one must apologize down here. Now, I know someone reading this is thinking, "are you crazy - even going back to antebellum times, concentration of wealth was prevalent in the South and less suspect." Ah, but I didn't say it was to be eschewed, I merely said apologized. Think of "Miss Daisy" from Driving Miss Daisy. She was in no way poor, but her mannerisms were contrary to displaying wealth. She would chide her daughter-in-law's showiness and act ridiculously frugal (guarding her canned vegetables ferociously!) When Mitt won't apologize for success, many of us exclaim with glee that someone is standing up for the right to use freedom and succeed against Obama's "Spread the Wealth", but Louisiana had that song-and-dance in political lead decades ago, in the form of Governor Huey P. Long, and his "Share Our Wealth Societies."
Finally, though I don't think it's as big of a factor in as it was in 2008, his Mormonism probably is more of a handicap here than anywhere else. As far as I'm concerned, the LDS are a form of Christianity, and he could be of any sect, or even agnostic, and if his positions and character were right, I'd support him. Still, some South Carolina exit polling did indicate he was still having a bit of a problem here. This is less relevant in a direct sense, and more relevant in how it situates the voting pools. If you don't want a Mormon, or a Slick Venture Capitalist, but you do want someone electable, Newt is able to try to pose - with his record as a Georgia Congressperson and his debate skills - as an alternative.
What's truly ironic is that the South has been so unwelcoming to Texas Congressman Ron Paul, who has seen liberal Vermont and conservative New Hampshire both give him over twenty percent in primaries - not caucuses! - and who has caucused better in the West. If you look at the internals of South Carolina, he did better in Appalachian counties - where the geography tends to invoke a rugged individualism. Paul had State Representatives endorsing him, and sung a States' Rights theme with a record to show this wasn't just Johnny-come-lately to Dixie, yet it was New England (home of the Hartford Convention ;) ) that seemed to welcome him. This post is less about Paul than Mitt/Newt, but as I support Ron Paul, I couldn't help but discuss him a bit.
I would suggest this has more to do with foreign policy. The South is a very hawkish area. Zell Miller crossed party lines in 2004 and asked whether Kerry's would-be administration planned to use "spit balls" due to its less friendly stance on military funding. Dr. Paul got booed for referring to a Golden Rule in foreign policy in South Carolina. Ironically, of all the candidates, Paul is the only protestant left in the race, but - in my opinion, much to his credit - he has declined to wear his faith on his sleeve. His faith guides him, but he has always held it informs his character much more than his policy, and his Oath to the Constitution comes first. Traditionalistic culture would make one much more receptive to invocations of religion, since religion serves as a legitmating force in culture. For all intents and purposes, in spite of his Catholicism (against which I hold no grudge, but historically was a handicap in much of the South), Santorum has taken the Evangelical role. Even with respect to schooling and health care - where Paul trusts localities and Christian charity more - Santorum's doubling-down on federal intervention if it's the "right" kind accords with Traditionalistic practice, since research shows Southern states actually tend to centralize education more than Individualistic states.
The irony is, if Mitt gets the nomination, it may be New England, LDS Romney who has the task of taking Virginia, North Carolina, and Florida back from Obama, and making sure Boeing has an unimpeded airspace through which to fly to its new, expanded production plant in South Carolina. I'd love for it to be Ron Paul - but not because he's a Texan, but because he has the better plan and commitment to take a blow torch to the Federal leviathan, cutting $1 trillion and 5 departments. If Romney is the nominee, I think it would be a real shame if his education, affluence, or regional and religious heritage were to hold him back in his conquest.
The record is fair game! :)
