It will take a lot for a Mitt Romney win to count as an actual win, if the results from Tuesday's primary contests are any indication. 

Rick Santorum (Creative Commons)

The former Massachusetts governor and former private equity chief locked in victories in at least five states, while his closest rival Rick Santorum secured three. As of now, Romney has 415 electoral delegates to his name, almost three times as many as Santorum. Romney is even back in the lead in national polls, if slightly.  

Romney seems to still be the likeliest candidate. Still, the headlines and morning-after analyses point to a long slog toward the nomination, for which the candidate needs 1,144 delegates and to trouble on the horizon come November. 

Here are some simple reasons:

The South:

No secret: Romney struggles in the Southern states, especially among Bible-belt conservatives, Tea-Partiers and evangelical voters, which Santorum won handily Tuesday. In March, Romney faces tough contests in Mississippi, Alabama, Missouri and Louisiana.

From the Wall Street Journal:

"I see Mississippi and Alabama as uphill battles for Romney,'' said Henry Barbour, a Romney backer and GOP official in Mississippi, who is also a nephew of former Mississippi Gov. Haley Barbour. "But we have an opportunity, by voting for Gov. Romney, to really help bring out the fat lady and end the nominating process.''

Santorum is for real:

Working-class voters, who do not appear to favor Romney enthusiastically, appear to like Santorum. The results breakdown from Ohio illustrate this. It was, after all, a very slim victory for Romney in what is widely expected to be a battleground state in the general election.

From Reuters:

Those hit hardest by the down economy appeared to have sided with Santorum over Romney in Ohio.

In CNN's exit polls, Ohio voters without college degrees and earning less than $100,000 voted for Santorum over Romney. Voters earning more than $100,000 and college-educated voters cast more ballots for Romney than Santorum.

A Demoralizing Campaign Process:

With Romney's war chest dwarfing everyone else's this campaign cycle, Santorum's staying power is striking. Some credit recent changes to campaign finance rules for Santorum's ability to stay in the race. 

A recent poll shows the long, negative race for the nomination may have a corrosive effect on the candidates' image. Romney's streak of negative campaigning is also seen by some as a bad strategic move in the long run before (if) he goes up against President Obama.

The campaign's newfound focus on social issues could distract from Romney's cornerstone economic message. 

This has liberal commentators ecstatic, with Ruy Teixeira declaring Super Tuesday a victory for Obama.

Reports Politico's Jonathan Martin:

Romney’s still likely to be the GOP nominee. But Super Tuesday demonstrated again that getting to Tampa is going to prove longer and costlier than he and his advisers had hoped — a predicament that has Republicans increasingly anxious and President Barack Obama’s high command downright gleeful.

Romney, though, has pointed out Obama had a long primary battle in 2008 and won decisively.  

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