Former Pennsylvania senator Rick Santorum’s dual wins in Alabama and Mississippi on Tuesday night hands his campaign some real momentum although he continues to fall further behind former Massachusetts governor Mitt Romney in the race for delegates.

What did we learn — or, more accurately, re-learn — from the votes last night in the South as well as in Hawaii and American Samoa? The five biggest lessons from the votes are below. What did you learn?

1. It’s a two-man race: Santorum’s wins in the deep South badly complicate former House Speaker Newt Gingrich’s logic for continuing on in the contest. Gingrich, never one to bow to electoral reality, seems to be committed to staying in the race for now — proclaiming in a speech Tuesday night that “the elite media’s effort to convince the nation that Mitt Romney is inevitable just collapsed.” Um, ok.

Regardless of whether Newt knows it or not, his chances of remaining a major player in this race effectively ended with his second place finishes in Mississippi and Alabama. Prominent conservatives have already begun to go public urging him to leave the race and that drumbeat will only grow louder if he refuses.

The question for Santorum is now that he’s got what he’s always wanted — a clear shot at Romney — can he deliver a win? In Michigan and Ohio — states where Gingrich was a total non-factor — Santorum started with leads and watched them evaporate amid a series of unforced errors and heavy spending from Romney and his Restore Our Future super PAC. If that pattern repeats itself in Illinois in six days time, Santorum’s last, best chance will disappear.

2. The math is the math....: Yes, Santorum won Alabama and Mississippi. But Romney won convincingly in American Samoa and Hawaii. That might not seem like a good night for Romney but from a delegate perspective it was.

According to delegate projections by the Associated Press, Santorum won eight more delegates than Romney in Alabama and Mississippi. But Romney netted 14 delegates over Santorum in Hawaii and American Samoa. That means that Romney won the night by 6 delegates, further increasing his already-wide lead over Santorum.

Again, according to the AP, Romney now has 494 delegates to 251 for Santorum. (Neither man is close to the 1,144 needed to formally clinch the nomination.)

Nothing that happened last night strengthened Santorum’s case that he has a viable path to that 1,144 number. Santorum still needs to win better than 60 percent of the remaining delegates to do so, a very unlikely prospect.

“[Romney] has twice the number of delegates as Senator Santorum and has received over one million votes more than Santorum in the GOP primary contests to date,” wrote Romney political director Rich Beeson in a memo distributed to reporters Wednesday morning.

3. ...But perception matters:Romney’s appeal to math may ultimately be determinative — the delegate numbers are what ultimately decides the identity of the nominee after all — and yet he clearly has a very large perception problem.

The presumptive nominee shouldn’t finish third in both major states that voted on Tuesday. The presumptive nominee should be able to win a state — any state — in the South. The presumptive nominee shouldn’t lose “very conservative” voters by 23 points in Alabama and 17 points in Mississippi.

But Romney did all of those things on Tuesday night, failing in what looked to be his best chance yet to beat back the “can’t win the South” and “can’t win among conservative evangelicals” storylines. By not shutting down that narrative, Romney ensured it would dog him for weeks (months?) to come even as it looks increasingly clear that Santorum simply can’t catch him in the delegate chase.

Politics is equal parts art and science. Romney is clearly winning the science argument — and will continue to do so. But, he has to find a way to win the “art” argument too. To be the frontrunner, you have to look like the frontrunner. And that means putting “W’s up on the board.

4. Illinois=Battle Royale: Illinois is the new Ohio. (Of course, Ohio was the new Michigan.) That is, Illinois, which is set to vote six days from today, will be cast — rightly so — as the next big thing in the Republican presidential race.

Illinois, unlike Alabama and Mississippi, is very much a home game for Romney — full of business minded Republicans attracted to his fiscal conservative bona fides. But, the state also has potential for Santorum — particularly downstate where religious and social conservatives predominate.

This is a state that Santorum and Romney both have to have. If Romney loses Illinois his math argument takes a hit as does the less-public-but-no-less-powerful argument that Santorum can’t win any state that the Republican nominee won't carry easily in the fall. If Santorum loses, he’s likely to be pigeon-holed as a candidate of the far right who can’t win any state where evangelicals and the base of the Republican base don’t comprise the majority of voters.

That reality ensures the next 6 days will be among the most brutal — and expensive — of the campaign. Sensing that Illinois might have to be a firewall state for Romney, Restore Our Future — the Romney aligned super PAC — is spending more than $1.4 million on TV ads in the state this week after spending better than $900,000 last week. No other candidate or super PAC had spent a dime in the state as of Tuesday night. Of course, Romney and his super PAC have outspent Santorum in every state that has voted so far — suggesting that money may not be the be all, end all of this contest.

5. It’s a game of “Survivor” now: While Illinois will serve as a critical test of strength for both Romney and Santorum, it’s hard to imagine the race coming to a close — symbolic or otherwise — after next Tuesday.

Santorum is already pointing to the March 24 Louisiana primary where he will now be heavily favored and, as we have written before, April looks to be Romney's best month yet in terms of the state’s set to vote. May holds good news for Santorum. June looks to be a good Romney month.

In short, the next three months could well amount to the equivalent of two boxers standing in the middle of the ring exchanging haymakers with neither man able to knock the other one down much less out. Both will have to weather bad patches in which a series of losses will force them to live off the political land for a time. Both will have streaks in which they appear to be unbeatable.

It’s certainly not the race Mitt Romney wanted but it’s the one he’s got. The question is whether he can survive and advance.

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