Former House Speaker Newt Gingrich speaks at the Alabama primary night rally Tuesday, March 13, 2012, in Birmingham, Ala. (AP Photo/David Goldman)

Newt Gingrich may not drop out of the race just yet, but his campaign for president is effectively finished. On Tuesday, Rick Santorum won both Mississippi’s and Alabama’s primaries. Gingrich came in second, but that’s not good enough. Last week Gingrich’s spokesman, R.C. Hammond, said they had to win both Mississippi and Alabama, and everywhere else in the Deep South to remain a credible candidate. “From Spartanburg [SC] all the way to Texas, those all need to go for Gingrich,” Hammond said.

On Super Tuesday Gingrich won only one state—Georgia, which he represented in Congress—out of ten. Santorum picked up several states and gave Romney a scare in the key battleground of Ohio. It is clear that Rick Santorum has firmly supplanted Gingrich as the leading conservative alternative to front-runner Mitt Romney.

This is especially so because of the geographic distribution of each candidate’s support. As this map of the results prior to Tuesday demonstrates, Gingrich’s support has been isolated to the South. The only states he won are South Carolina and Georgia, and the only counties he won elsewhere were in Northern Florida and a few spots in Oklahoma. Romney dominates the Northeast, Southwest and urban Midwest. Santorum wins the rural Midwest and Great Plains.

This didn’t give Gingrich a plausible path to the nomination. But if he won Mississippi and Alabama, he could have stayed in the race as a potential power-broker. A Republican who wins all the Deep South primaries has a credible claim to represent the heart of the party’s base.

But Gingrich can no longer claim to represent the soul of the GOP any more than Santorum. Santorum won Tennessee and Oklahoma on Super Tuesday, and so he is as much the South’s preferred candidate as Gingrich. Unlike Gingrich, Santorum also has won or come in a close second in many states outside the South.

When Gingrich comes to the South, he deftly deploys culture war appeals. It worked in South Carolina. He tried it again this past week. But it didn’t work well enough this time. Republicans—especially the ultraconservative in the South—badly want to beat Barack Obama, and they know it’s time to narrow the field.

The Gingrich campaign maintains they are still in the race. Speaking on MSNBC, Gingrich’s daughter Jackie said Tuesday’s results show “we’re still very strong.… we’re moving on to Illinois and Louisiana.” So they’re not dropping out for now. Gingrich, addressing supporters in Birmingham, insisted he intends to go all the way to the Republican convention in August. Since Gingrich came in second in both states, he portrayed the night’s results as proof of Romney’s weakness. “If you keep coming in third you’re not much of a front-runner,” Gingrich cracked. In a typical Gingrichian flourish, he noted that “the conservative candidates” won 70 percent of the vote, and that “the elite media’s effort” to declare Romney’s nomination inevitable is incorrect. He delivered these lines, and most of his speech, with a scowl on his face.

But Gingrich looked gleeful recounting how the Obama administration has become defensive on the price of gasoline, thanks to Gingrich’s preposterous promises that he would lower gas to $2.50 per gallon. As Jackie correctly noted on MSNBC, “my father is the only Republican driving the conversation,” pointing to Obama’s responses to Gingrich on gas prices.

That’s true enough. But it is nothing of which he should be proud. Gingrich is making a stupid, nonsensical argument, and in doing so he is damaging what is left of his shredded reputation for intellectual seriousness.

Michele Bachmann made an equally loony promise to reduce the cost of gasoline to less than $2 per gallon through increased drilling. The problem is that petroleum is a fungible commodity and the price is set by global supply and global demand, not merely domestic production. Moreover, the United States uses roughly 25 percent of the world’s oil, while it has only 2 percent of the world’s proven oil reserves. Anyway, domestic oil production has risen under Obama. Bachmann may have the excuse that she does not know or understand these facts. Gingrich probably does understand how commodities markets work, but he is acting like a moron to get attention.

It may be hard to remember now, but before he ran for president Gingrich had largely reinvented himself. He had resigned as Speaker of the House as a disgraced, unpopular embarrassment to his party. For a decade Gingrich tried to revive the more appealing aspect of his public persona: the earnest futurist wonk. He worked in think tanks and advocacy groups, wrote books and articles, and partnered with Nancy Pelosi on climate change and Al Sharpton on education reform. If Gingrich hadn’t run for president, it might not have been outside the realm of possibility that he could receive an appointment from the next Republican administration. If nothing else, he would have had some influence from his perch at the American Enterprise Institute and Fox News.

Instead, Gingrich’s campaign reminded everyone of his most unsavory characteristics. It brought renewed attention to his serial infidelity. Mitt Romney lambasted his lobbying for Freddie Mac. Gingrich made polarizing appeals to racial resentment. The entire Republican establishment came out to squash his candidacy, publicly reminiscing about his poor leadership in the House. He will leave the campaign, whenever that happens, as a divisive has-been.

Santorum’s wins do not mean Romney is no longer the most likely nominee. Romney won the Hawaii primary, the caucus in American Samoa and some delegates from his reasonably close third-place finishes in the South. He remains far ahead in total delegates.

Contrary to what some have suggested, Romney will not select Gingrich as his running mate. Aside from the fact that the two men clearly hate each other, no one would choose a running mate with Gingrich’s liabilities. If there is a Romney presidency, Gingrich will be on the outside.