Mitt Romney - the old reliable - returned to form in South Carolina on Saturday, capturing just 27.8% of the Republican vote.  Or is Vapid Mitt the captive of the quarter to third of the GOP electorate that is oh-so comfortably moderate?  Good question, and Florida's GOP voters may end up giving us the answer.

New Hampshire may just prove to be Romney's high water mark - New Hampshire, that is, backyard to Mitt's home state of Taxachusetts.  If Romney couldn't win in The Granite State, where can he win?              

Here's the conventional wisdom on the upcoming Florida Republican primary, as expressed by the Washington Post's Dan Balz.  Balz writes: "Florida presents a major challenge [to GOP contenders Mitt Romney, Newt Gingrich, and Rick Santorum, principally], given its size and complexity."

The Sunshine State may present challenges in terms of size and complexity in a general election fight, but a primary battle - Republican or Democrat - is a different critter.  The bulk of the state's 4.1 million registered Republicans are along the I-4 corridor (that's Tampa-St. Petersburg-Sarasota through Orlando-Daytona Beach-Melbourne) and Florida's northern tier -Jacksonville west through the Panhandle.  Miami-Dade and Broward County have a much smaller, but significant, concentration of Latino GOP voters.  

An estimated 1.9 million Florida Republicans voted in the 2008 GOP primary.  More Republicans may vote this time.  MSNBC reports that about 185,000 Republicans have already voted absentee.  The absentee votes may break Romney's way, given that these ballots were cast prior to South Carolina.     

Early voting has begun in Florida, and having begun on the heels of Newt Gingrich's thumping victory in South Carolina, expect the early vote to trend Gingrich's way.

Romney's challenge - and dilemma - in Florida is no different than elsewhere (save New Hampshire).  Romney needs to find a way of attracting conservative votes.  25% to 30% of a bigger GOP universe is still 25% to 30%. 

Romney needs to hope that Santorum puts on his rally cap and sops up his share of the state's conservative vote, thereby depressing Gingrich's totals.  Romney's Last Man Standing strategy critically relies on division among conservatives.  If Gingrich carries strong momentum into Florida (likely at this writing) and doesn't make any major mistakes, Romney's got a world of trouble.

Florida's northern tier is Gingrich Country, in that it borders Georgia and Alabama.  North Florida voters generally profile like their southern neighbors - economically and socially very conservative and strongly religious (with Southern Baptists dominating).  Many are gun owners and hunters who take the 2^nd Amendment as gospel.  Gingrich began his political career in west Georgia, which profiles like north Florida.  Gingrich knows well how to campaign among this voter segment.

The Miami-Dade and Broward County Latino Republican voters are solid social conservatives, which should be particularly helpful to Santorum.  Romney's social conservatism lacks conviction and comes off as platitudinous.  The challenge for Gingrich is to outmaneuver Santorum and win among Latino social conservatives.

The GOP primary decider will be along the I-4 corridor.  Romney needs suburban Republicans in Tampa, St. Petersburg, and Orlando to turnout heavily for him.

Gingrich's advantage in the I-4 corridor fight is Bill McCollum, a staunch conservative and longtime central Florida congressman and former state Attorney General.  McCollum has endorsed Gingrich, and brings his network into play for him. 

Romney, of course, has money and organization in place.  But money and organization didn't avail Romney in Iowa (note to Karl Rove: Romney lost Iowa by thirty-four votes).  And Romney's money failed him in South Carolina. 

Gingrich's strategy in Florida is simple enough: provide meaningful contrasts with Romney, fire away at President Obama (especially over proposed defense cuts, Florida's lagging real estate market, and Obamacare, which robs money from Medicare), and crowd out Santorum among social conservatives. 

Simple, but not easy, but doable for Gingrich - more doable than Romney's need to break out and win conservative voters... something that Romney has failed to do previously.