Everyone paying attention to politics at this point in the cycle has read at least a dozen different mathematical calculations on how improbable it is for anyone other than Mitt Romney to win the Republican nomination for the presidency.  While some of those equations make sense, only one thing is certain: Mitt will definitely prevail if the field is not narrowed further soon.

A primary/caucus ballot absent either Rick Santorum or Newt Gingrich doesn't guarantee a victory for the not-Mitt, but the arrangement does allow for those very circumstances.  The math in Florida speaks to this: Mitt got 47% of the vote while Santorum (13) and Gingrich (32) got 45%.

The problem is, as it almost always is in politics, that we are dealing with egos, not math.  But an objective look makes it clear, between Gingrich and Santorum, who should go and who should stay.

Of the two candidates, it is Newt who has been mortally wounded.  In another era, he might be able to recover, but an arrogantly hostile media, a glaring lack of organization, and the absence of any broad supply of money won't give him the time and resources to do that.  His negative favorability numbers are so embedded in the equation that even the most organized and lavishly financed campaign would have difficulty making them move.

This is not to say that Newt is not the best person to be the candidate to run against the president, or that he is not the best in the field to serve in that office.  That's not the issue.  What's important is that from where Newt is now to where he has to go is just too far.  Newt has been damaged beyond repair.

Santorum, despite being in the race even longer than Newt has, doesn't have any deep wounds.  Never a priority target because he too lacks organization and funds, he's remained more or less unscathed.  Though this would change if he were Mitt's one real opponent, there's little in his closet that will jump out and drag him down.  This leaves Santorum free to devote himself to offense far more than to defense.

With his wife and seven kids by his side, Rick Santorum has got a reservoir of symbolism that protects him from much of what Newt has to overcome every day.  In addition to this, Santorum has some constituencies that are yet to be heard from.

• First and foremost, he's a more natural heir to the Tea Party mantle than Newt is. If a revival of the Tea Party'sfever-pitch of 2010 is going to happen, Santorum is more likely to be part of that than Newt is -- and certainly more than Romney would be. Santorum is of the Tea Party; the other two are not.

• Rick's roots are in that part of the Republican Party that were known as Labor Democrats during the Nixon years. They were the famousPeripheral Urban Ethnic majority that the Nixon staff found and focused on. Santorum still speaks to that piece of the party in Pennsylvania and throughout the battleground industrial Midwest. Though this demographicparted with Santorum in his last election in Pennsylvania, he's won them before, and he can do it again.

• Rick Santorum is Italian. Not many people are aware of that...yet. Ethnic voting isn't what it used to be, but Rick Santorumcan revive it in Italian enclaves and a bit beyond.

• The Santorums' large family and religious background speak to Catholics, and the Obama administration just united that constituency in opposition to Obamathis past week. Santorum can tap into this in a way well beyond both Newt's and Romney's capabilities. Opposition to ObamaCare has just taken on a newpriority inside the Catholic Church, aninstitution that supported it the last time around.

• He's got the "not-moneyed-guy" vote. Mitt's wealth and Newt's Tiffany charge accounts won't let them easily grasp that newly createdrole. Whatever Rick has as his net worth, he doesn't come across as a wealthy man. No doubt the Obamas' thirteen-million-dollar income last year will be sculpted into a 527 headline that will compare better for Santorum than it will for Mitt or Newt.

• Santorum's got a piece of the wonk vote. While not Gingrich, he can go deep into an argument if he needs to and won't be out-debated. Presented strongly, Santorum's positions on a number of issues will command respect. His legislative experience will match Obama's teleprompter overview, and his depth might be an upside surprise for most of the electorate.

• Obama's projected deep military cuts make the military astronger constituency forSantorum as well. Instead of just getting their votes, Santorum has the opportunity to mould our men and women in uniform into a vibrant voting bloc. He's demonstrably sound on things like veterans' affairs, military families, and the well-being of our troops. Even Democrats in the military are likely to cross over to him on these issues.

• Santorum is as strong on Israel as any candidate we've seen on the Republican candidate list, and that says a lot. Both Jews and Evangelicals can coalesce around his advocacy for Israel.

• Economics. Santorum's ego rarely gets in the way of his policy decisions, and he's readily able to acquire other positionshe thinks are right. His ego doesn't demand "his" plan to move forward, and a Paul Ryan-type plan could fit nicely into his past efforts on economic growth.

• Energy. Santorum's Pennsylvania base, with its coal and energy production, gives him a natural affinity for the development of domestic energy. In the wake of the Obama administration's deficit in this area, Santorum has the credibility to push this issue easily to the forefront.

One of the things Santorum needs, though, is help.  If all of the above can be pulled together, he'll need to upgrade his staff immediately to truly make it happen.  He needs the professionals around him who can help him win.

One example of this critical need is "the vision thing."  This is something that isn't a staple of House or Senate elections as much as it is in presidential contests, and there's much more that goes into it than just better speechwriting.

Right now Obama is working on his own version of the vision thing, trying to reinvent himself.  He and his billion-dollar budget might be able to do that, but besides selling his new vision, he has to get folks to disregard the old one.  This leaves an opening for the Republican "City on the Hill" type of message -- that is, spirited themes that will move the electorate.  Rick Santorum needs a strong team who has done this before.  He needs a Panama Canal (Reagan in '76) and the people to find it for him.

If Rick Santorum is truly ready to step up to the presidency, and if he has the country at heart, he'll have to go where he hasn't gone before and fully staff as soon as possible.  That's why it is so important to clear the field now and not in May.

Romney is not inevitable, and what's more, Obama is not either.  Yet Newt Gingrich is the only one who can swing the odds against both of them.  Newt alone can allow us to turn towards Santorum and remove the Obama from office.

N. Richard Greenfield heads Ledger Publications in Hartford, Connecticut, which publishes weekly and monthly newspapers in Connecticut and Massachusetts. He has been active in politics for many years and has worked on a number of campaigns around the country.