By MICHAEL FALCONE ( @michaelpfalcone ) and AMY WALTER ( @amyewalter )

CHARLESTON, S.C. - Will the results of today's voting in South Carolina all but secure the Republican nomination for Mitt Romney or will it kick off a long, messy slog to the winner's circle?

We will know a lot more about that question when polls in the "First in the South" primary state close at 7 p.m. ET tonight.

After a roller-coaster week, four candidates are left jockeying for a ticket out of here, with Romney and challenger Newt Gingrich locked in a fierce fight over who will win the right to take on President Obama in Nov. 2012. But Rick Santorum and Ron Paul are still in the hunt too and one thing the lead-up to today's contest has showed us is that anything can happen.

As ABC's Matthew Jaffe notes, "When the candidates left New Hampshire just last week, Romney was flying high, fresh off a resounding win in the Granite State and believed to be a narrow 8-vote victor in Iowa's Jan. 3 caucuses. Gingrich, meanwhile, was struggling after two disappointing showings to kick off the primary."

How things have changed.

"As voters head to the polls today, Gingrich, not Romney, is now the favorite," Jaffe writes. "Two commanding performances by Gingrich in the past week's debates helped. So too may have the fact that he hails from neighboring Georgia. Not even his ex-wife's claims that he lacks the moral character to be president slowed him down." http://abcn.ws/zwu45U

Not only that but overnight, the Iowa Republican Party blasted out an e-mail message declaring, once and for all, Santorum as the winner of the Iowa caucuses.

All of this raises the possibility that we could have three different candidates win the first three nominating contests. That's one for the history books. And keep this in mind: "Since 1980, no Republican has won the Presidential nomination without first winning South Carolina," Chad Connelly, chairman of the South Carolina GOP, told ABC News.

Voting has already begun in the Palmetto State and only time will tell whether the state's political motto - "We Pick Presidents" - comes true this year.

On "Good Morning America" today ABC's Jonathan Karl reported from Charleston, S.C. about the clash between Romney and Gingrich for the top spot in South Carolina this week. WATCH: http://abcn.ws/wMUIGR

PRIMARY PRIMER: All details about what to expect from today's contest from ABC's Elizabeth Hartfield:

DELEGATES AT STAKE: Twenty-five delegates are up for grabs in Saturday's contest. That number represents a 50% reduction of their original 50 delegates. The state was penalized for moving its primary date ahead of Feb. 1, a move made to preserve South Carolina's status as the first primary in the South after Florida jumped the line and moved its primary date to Jan. 31.

THE LANDSCAPE: As of Jan. 1, 2012, South Carolina counted 2,722,344 registered voters - 79% of the voting eligible population of 3,434,551. In South Carolina, voters do not register by party, so any registered voter can participate in the Republican primary.

COUNTIES TO WATCH: Two key counties to watch out for in Saturday's primary are Greenville and Lexington. Located in the northwestern part of the state, Greenville is South Carolina's most populous county. The county has a history of favoring socially conservative candidates. George W. Bush dominated Greenville in 2000 with 58% of the vote, and Mike Huckabee carried it in 2008, with 29% of the vote to McCain's 26%. Romney received 17% of the votes in Greenville in 2008, and his performance in this cycle will be a telling mark of whether he's been able to successfully court the social conservative vote. Greenville will also provide a window into the Gingrich and Santorum battle, particularly in light of Rick Perry's recent departure from the race. The former Pennsylvania senator and the former House Speaker are both vying for that spot as the anti-Romney candidate around whom the socially conservative base coalesces.

PRIMARY FACTS: BY THE NUMBERS , courtesy of the South Carolina Republican Party:

4: Number of Presidential debates held in South Carolina (Greenville, Spartanburg, Myrtle Beach and Charleston)

$20,000,000: Estimated direct economic impact due to the Presidential Primary, much of which was generated by out of state dollars. Television ads, debates, hotel rooms, staff hires, gasoline, mail pieces, etc. contribute to this number.

450,000: Number of estimated voters on January 21

9: Number of candidates on the ballot in South Carolina (deadline for name removal was December 1, 2011): Newt Gingrich, Ron Paul, Mitt Romney, Rick Santorum, Michele Bachmann, Herman Cain, Jon Huntsman, Gary Johnson, Rick Perry

33%: Statewide percentage won by John McCain, the winner in 2008

20%: The combined percentage of statewide votes found in Greenville and Spartanburg Counties

65%: The combined percentage of statewide votes found in ten critical counties

DEMOCRATIC COUNTER-PROGRAMMING. As voters head to the polls to choose a presidential candidate to take on President Obama in November, Democratic National Committee Chairwoman Debbie Wasserman Schultz and Democratic National Committee Executive Director Patrick Gaspard will stop by an Organizing for America South Carolina (OFA-SC) 2012 Action Meeting in Columbia to address volunteers as they work to build President Obama's grassroots movement in South Carolina. When? 10:30 a.m. Where? Tony Thomas Family Karate Center,  130 Fontaine Center Dr., Columbia, S.C.

WHAT SOUTH CAROLINIANS HAVE BEEN WATCHING: A BARRAGE OF ADS: Voters in South Carolina have been subjected to a non-stop bombardment of political ads during the primary season. Here's what a viewer in Charleston, S.C. saw if they had been watching the local evening news on an ABC affiliate last night. During the course of three commercial breaks no fewer than 18 political ads aired, including seven sponsored by super PACs supporting one of the candidates and 11 commercials paid for by the campaigns, themselves. According to some reports, the campaigns and the super PACs spent a combined $13 million on television ads in South Carolina during the primary season, and in the remaining hours before voters go to the polls, that is translating into a non-stop stream of political messages.

Here's a glimpse of the onslaught during just one 30-minute period on local television: During the first commercial break alone, viewers saw six political ads: Restore Our Future super PAC (pro-Romney) ad attacking Gingrich; Gingrich campaign positive ad; Romney campaign positive ad; Paul campaign positive ad; Citizens For A Working America super PAC (pro-Romney) ad; Santorum campaign negative ad (anti-Romney). During the second commercial break viewers saw 10 - count them, 10 - political ads: Santa Rita Super PAC (pro-Paul) positive ad; Red, White and Blue Fund super PAC (pro-Santorum); Ron Paul campaign positive ad; Gingrich campaign positive ad; Winning Our Future super PAC (pro-Gingrich) ad; Santa Rita Super PAC (pro- Paul) positive ad (same one as above, aired twice); Santorum campaign negative ad (anti-Romney); Gingrich campaign positive ad; Romney campaign positive ad; Paul campaign negative ad (anti-Gingrich). During the post-local news commercial break viewers saw two political ads: Gingrich campaign positive ad; Restore Our Future super PAC (pro-Romney) anti-Gingrich ad.

 

THE BUZZ

ROMNEY CAMP LOOKING TOWARD THE SUNSHINE STATE. "The Romney team knows there is a good chance they could leave South Carolina without a victory, so they have begun looking to Florida as a defining moment in the campaign, and nothing less than a 'must win,'" ABC's John Berman reports. "With the stakes so high, the Romney campaign has been working to line up what would be one of the last remaining All-Star endorsements: Jeb Bush, the former Florida governor.  Multiple Florida insiders say that calls have been going back and forth.  If things do not go well for Romney in South Carolina, Jeb Bush, the former Florida governor, could be just the thing to cure the candidate's election blues. Though nothing is currently set in stone in Florida, Bush's father, former President George H.W. Bush, has already voiced his support for Romney. More good news for the Romney team: Florida is a state where they feel very well positioned. They have an enormous financial and organizational advantage there, and they are prepared to flex it big-time." Berman has more on what to look for from the Romney campaign in the coming days: http://abcn.ws/wLxQbV

ROMNEY'S RAUCOUS PRIMARY-EVE RALLY. ABC's Emily Friedman repors that Romney held one of the liveliest rallies of his presidential campaign in Greenville, S.C. last night, speaking to a crowd who could barely hold back their cheers of support as the candidate vied for votes in the final hours of primary day eve. The rally, which packed at least 300 people into the room, came after a week of some less impressive events, including a rally in Florence, S.C., earlier this week when photographers captured a half-empty ballroom waiting for Romney's speech. But earlier today it seemed that the momentum, despite the shrinking gap in the polls between Romney and Gingrich, was picking up again for the former Massachusetts governor, when a crowd of a few hundred stood in the rain at a tree farm to attend an outdoor rally. When the crowd broke into chants  of  "We need Mitt! We need Mitt! We need Mitt!" Romney responded frankly, "Do you know what? You're going to get me." …  "I simply don't think that the people of America will choose a lifelong politician who have spent their entire career in Washington to replace the lifelong politician who spends his time in Washington," said Romney. "I think they have to have someone who has had experience in the private sector, who knows how the economy works, and who can bring that experience to post up to Barack Obama." http://abcn.ws/xjdeth

DIRTY TRICKS TARGET NEWT GINGRICH. Newt Gingrich came under assault yesterday from shadowy forces trying to blunt his appeal in the Palmetto State. Unknown opponents of Gingrich spent Friday employing a variety of dirty tricks against him beginning with a fake CNN e-mail news alert that read: "A source close to Marianne Gingrich tells CNN that former House Speaker Newt Gingrich forced her to abort a pregnancy conceived during the affair that preceded her marriage to Gingrich." The mock news alert was followed by a fake press release made to look like it was sent by Gingrich's campaign responding to the doctored CNN message. Under the dateline, "Orangeburg, SC" - the location of one of Gingrich's Friday campaign stops - the faux release began: "Newt Gingrich released the following statement regarding reports that he forced ex-wife Marianne Gingrich to terminate a pregnancy" It looks very similar to the actual press releases the Gingrich campaign sends out on a daily basis, including the campaign logo and typefaces. It also includes the name and e-mail address for Gingrich's press secretary, R.C. Hammond. It includes a fake quote from Gingrich: "I am not proud of some decisions I have made or actions I have taken, but I believe in the power of redemption and I trust the voters of South Carolina do as well." http://abcn.ws/zbf7g1

NOTED: South Carolina GOP Chair Chad Connelly on dirty tricks: "It's pretty tame compared to what we've seen in the past."

SANTORUM STRESSES NATIONAL SECURITY MESSAGE.  Speaking before a crowd that included a number of cadets from the Citadel on Friday night, Rick Santorum warned that "radical Islamists" pose as great a threat to the Islamic world as they do to the United States, if not greater, ABC's Arlette Saenz reports. He argued that the next president will have to take a more active role in working with people in countries such as Iran to help them combat the dangers inflicted by radical Islamists. "There is an existential threat out there. It is a threat that has challenged Western civilization for 1300 years," Santorum said in a keynote speech at the Patriot Awards Dinner hosted by the Citadel's Republican Society. "In its most virulent form, it is back, and it is funded by oil. If we do not put together a strategy to defeat that radical element within the Islamic world, that threatens the Islamic world more than it does even us. Look at the Iranians. I send a message all the time to the Iranian people. Hold on hold, continue to fight. We will help you. We will help you get rid of these tyrants that are destroying your life and destroying your country. These radical Islamists who are oppressing people and torturing them and killing them and robbing them of every bit of dignity in the name of this radical theology. Look at the people who are most affected by these radical theocrats. It's not the West. It's within that region of the world." http://abcn.ws/x6iX97

RON PAUL'S LONG BALL STRATEGY. The latest step in Rep. Ron Paul's long-ball, 50-state strategy looks like an animated semi-truck, honking and barreling through Minnesota's TV airwaves, notes ABC's Chris Good. Paul's campaign today announced a "substantial" purchase of airtime in the mostly ignored caucus state of Minnesota, the site of Paul's 2008 counter-convention as Sen. John McCain received the GOP nomination. The purchase is another installment in Paul's plan to seize caucus states where other candidates haven't campaigned, and it follows airtime purchases for four separate TV ads in Nevada, announced in October. Paul has already spent money on direct mail in the caucus states of Nevada, Maine, Colorado, North Dakota and Washington, as well as Louisiana, ABC's Jonathan Karl reported this month. The Minnesota GOP could not confirm that any other candidate is running TV ads in the state. http://abcn.ws/AjgTVk

 

WHO'S TWEETING?

 @mollyesque : Today's Charleston Post & Courier, the South's oldest daily. pbckt.com/pT.QYHqrS

@markzbarabak : Mitt causes a Tea Parting: Haley's SC endorsement points up schism within the anti-establish movement  #GOP2012  #fits  lat.ms/xGgb66

@pfeiffer44 : Its unfortunate that the House GOP has decided to spend 2012 attacking the President instead of helping the economy nyti.ms/wcRDCF

@jeffzeleny : A great today read from  @sherylstolberg: Wives Always at the Center of Gingrich's Career.  nyti.ms/yFvTcn

@PeterHambyCNN : let the record show: Newt spokesman  @RCHammond called South Carolina the campaign's "firewall" way back on Oct. 12  bit.ly/pAjgx2

POLITICAL RADAR:

- Mitt Romney will start primary day in Greenville, South Carolina with a visit to his campaign office. Then, Romney will meet with voters at Tommy's Country Ham House in Greenville. Romney will watch the results come in Saturday night from the South Carolina State Fair Grounds in Columbia.

- Newt Gingrich will also pay a visit to Tommy's Country Ham House in Greenville at the exact same time rival Mitt Romney is scheduled to meet with voters. In addition to Greenville, Gingrich will campaign in Spartanburg, Anderson and Laurens. Gingrich will hold his primary party in Columbia at the Hilton Hotel.

- Rick Santorum is on the trail in Chapin and Greenville where he'll talk to voters at two polling locations. Santorum heads to Charleston in the evening to watch the votes come in from Citadel College.

- Ron Paul will campaign during the day in South Carolina and head to Columbia in the afternoon for his primary party. Paul will gather with voters in Columbia at Jillian's Billiards Club.

-ABC's Josh Haskell (@HaskellBuzz)

Check out The Note's Futures Calendar:  http://abcn.ws/ZI9gV

 

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