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

Each of the Republican candidates begins this primary day with something to prove.

Mitt Romney wants to show he can win in the Deep South - territory that would seem unfriendly to him, but where polls indicate a razor-thin race.

Newt Gingrich needs at least one victory to make good on his recent prediction that, "I think we'll win both" Alabama and Mississippi.

Rick Santorum would like to deny his rivals an opportunity to add to their delegate total. His campaign circulated a memo yesterday outlining a path to a prevent Romney from clinching the nomination before this summer's Republican National Convention.

And Ron Paul is still looking for his first state win. He has been sending surrogates to Hawaii, which hold caucuses today.

There's been no recent polling in the Aloha State, but Paul's son, Ronnie; Santorum's daughter, Elizabeth; and Romney's son, Matt, have all campaigned there this week, suggesting that it will be a competitive contest.

Alabama and Mississippi are the big prizes and the candidates have the most at stake in those two states.

Wins in both places would help Santorum solidify his standing as the "undisputed" conservative alternative to Romney. Gingrich could show he can do well outside of Georgia and South Carolina. And, Romney could put to bed the narrative that he can't gain tractions in states with large Evangelical populations.

Romney may also be helped by the fact that Gingrich and Santorum are going to split the very conservative vote, giving him the opportunity to squeak by with one win - or even two.

Regardless of what happens tonight, Santorum and Romney's campaign schedules today make it clear that they are plowing ahead to the next contests.

Santorum will be hosting an election night party in Louisiana, a state that hosts its primary on March 24. Romney will be spending the day in Missouri, which caucuses on March 17. Gingrich is in Birmingham, Ala. tonight, but tomorrow heads to Illinois to campaign ahead of the state's March 20 primary.

ABC's Elizabeth Hartfield and Chris Good contributed reporting.

On "Good Morning America," ABC's Jonathan Karl explored the political landscape in the South as voters head to the polls there today. WATCH: http://abcn.ws/A4gDjC

PRIMARY PRIMER.

by Amy Walter, Elizabeth Hartfield, and Chris Good

States/Territories Voting:  Alabama, Mississippi, Hawaii and American Samoa

Total delegates at stake: 119 - 75% of which come from Alabama and Mississippi

Earliest poll closing: 8pm (Alabama/Mississippi)

Latest poll closing: 2 am (Hawaii)

Super PAC Spending: "Restore Our Future," the group supporting Romney, has spent the most money by far: $1.3 million in Alabama and roughly $940,000 in Mississippi, according to their FEC disclosures. The figures for "The Red, White and Blue Fund," the group supporting Rick Santorum, and "Winning Our Future," the group supporting Gingrich are much lower than Restore Our Future, but they're still significant. The Red, White and Blue Fund has spent $275,000 on ad buys in Alabama and $223,000 on ad buys in Mississippi. Winning Our Future has spent a little over $299,000 in Alabama, and a little over $240,000 in Mississippi, per FEC disclosures.

Quote of the Day: "If you don't win the South, you don't win the nomination." -Sue Everhart, chair of the Georgia Republican Party.

 

VIDEO OF THE DAY: SPINNERS AND WINNERS. What the Congressman Whispered to the President: Outgoing congressman Dennis Kucinich says his legacy is being a "siren" against war. WATCH: http://yhoo.it/xRDM79

 

THE BUZZ

SANTORUM SAYS MITT ROMNEY LIVES IN AN 'IMAGINARY WORLD' Rick Santorum lashed out at Mitt Romney as "sad," "desperate" and living in an "imaginary world" for suggesting he is too liberal to be Romney's running mate should the former Massachusetts governor become the Republican presidential nominee. "I'm too liberal?" Santorum said in an interview with ABC News' Jonathan Karl. "This is the imaginary world of Mitt Romney's ideology. It's just sad." Calling Romney "one of the most liberal records ever to run in the post-Reagan era for president," Santorum said: "If I am too liberal to be Mitt Romney's running mate, oh my goodness. That just tells you how desperate he is." Santorum was referring to an interview Romney did Monday with Neil Cavuto on Fox News. Cavuto asked Romney whether he would have to pick a running mate more conservative than he is to satisfy Republicans who think he is too moderate. "That would preclude, of course, Rick Santorum," Romney told Cavuto. "Rick Santorum is not a person who is an economic conservative to my right." Romney added: "I give him credit for being a conservative, but not a fiscal conservative. His record suggests that he does not have the fiscal conservative chops that I have." http://abcn.ws/we0sFJ

ROMNEY TALKS UP FRIENDSHIPS WITH NFL TEAM OWNERS. Roughly two weeks after taking heat for noting during an appearance at the Daytona 500 the he has "some friends who are NASCAR team owners," Mitt Romney once again attempted to play up his everyman credentials. But once again, it may not have been the message he wanted to send. "I've got a lot of good friends - the owner of the Miami Dolphins and the New York Jets - both owners are friends of mine," Romney said in an interview with an Alabama radio host Paul Finebaum on Monday. Near the end of an 11-minute interview that focused on sports and politics, Finebaum asked Romney about NFL free-agent Peyton Manning. "I'm surprised to hear that Denver's thinking about him," Romney said, adding: "Let's keep away from New England so that Tom Brady has a better shot of picking up a championship for us." Miami Dolphins owner Stephen Ross and New York Jets owner Woody Johnson are publicly supporting Romney and have been raising money for the former Massachusetts governor. http://abcn.ws/x7zt1P

NOTED: Despite reaching the Medicare-eligibility age on his 65th birthday yesterday, Mitt Romney will keep his private insurance and forgo the social safety net, a Romney aide said today, according to ABC's Z. Byron Wolf and Emily Friedman. The GOP presidential front-runner has used Medicare as a campaign issue, proposing to curtail future benefits for wealthy people like him so "lower-income seniors would receive the most generous benefits." Romney has proposed raising the eligibility age for all Americans to enroll in Medicare. But his proposed changes, outlined at a speech in Detroit last month, would not take place until 2022, and so would  not affect anyone now approaching Medicare or Social Security. He proposes tying the future enrollment age for Medicare to the average life expectancy of Americans. http://abcn.ws/zgeOPZ

PRIMARY STATE SPEED READ.

by ABC's Chris Good

-Low Turnout Expected in Mississippi. County officials in Mississippi tell the Clarion Ledger the expect light turnout in today's primary compared to 2008, based on relatively few absentee votes cast so far. http://on.thec-l.com/yHAyUb

-Candidates Poised to Split Alabama's Delegates? Without reliable polling, no one really knows where the race in Alabama stands. But some expect it to be close, and the Birmingham News reports that if it is, Mitt Romney, Newt Gingrich, and Rick Santorum will likely split the state's 50 delegates evenly, given how the state's proportional allocation system works. http://bit.ly/AFx35p

-Santorum, Gingrich Address Packed GOP Forum in Alabama. Mitt Romney didn't participate, but the two leading alternatives campaigned in Birmingham Monday night at a forum hosted by the Alabama GOP. The candidates delivered familiar stump material conservative social values and lower gas prices. http://bit.ly/AxxSp7

-Jeff Foxworthy's Serious Pitch for Romney. If you make an appearance on Mitt Romney's behalf at Shaggy's restaurant in Biloxi the day before the Mississippi primary, but instead of telling jokes express concern about the direction of the country, you might be comedian Jeff Foxworthy. The Georgia native also had some tough words about Newt Gingrich, telling the Biloxi Sun Herald: "I have seen him put his foot in his mouth, do or say something stupid too many times. So it's one of those cases of you reap what you sow. I'm not confident putting my eggs in that basket. If he does something like that in September, then we are shot and we're stuck with four more years of this. We can't do four more years of this. The country will be bankrupt." http://bit.ly/wVSgeP

-Mississippi Voters Sick of Robocalls. They're so sick, in fact, that Public Service Commissioner Leonard Bentz said his office got 35 complaints from voters on Monday. There's little he can do: political calls are exempted from the state's do-not-call registry, and an anti-robocall bill failed to advance in the state legislature. http://bit.ly/wEJRCV

-Santorum on Drilling: 'I Didn't Change as the Climate Changed.' Rick Santorum and Newt Gingrich took turns assailing President Obama over high gas prices at a forum in Biloxi, Miss., on Monday-but Santorum worked in a dig at his rivals Newt Gingrich and Mitt Romney for steps they took to acknowledge global warming. "We need someone who didn't buy into that environmental hoax of man-made global warming," Santorum said. "I opposed any cap-and-trade, unlike other people in this race who sat on couches with [Pelosi] or crowed when they were governor of Massachusetts about imposing the first carbon tax. And warning against the dangers of carbon dioxide, calling it a toxin. Tell that to a plant. We had rational individuals on our side jumping onboard, including [Gingrich and Romney]. I didn't change as the climate changed. Now the climate has changed back and everybody's for drilling. When times were tough, they were not and I was," the Biloxi Sun Herald quotes Santorum as saying. http://bit.ly/zs3E6a

-Romney Won't Pick Favorite Between Alabama and Auburn. Talking sports with Alabama's most popular radio program, the former Massachusetts governor made a safe play and declined to wade into Alabama's biggest-and most bitter-collegiate rivalry. "I have to look at the Alabama programs with envy. I'm not entering the controversy of who I'd pull for, Tigers or Tide," Romney told the Paul Finebaum Radio Network, which is syndicated across the South and carried by Sirius XM satellite radio. http://bit.ly/AmWxmk

 

IN THE NOTE'S INBOX:

-GROUP BEHIND "KONY 2012? VIDEO ADDRESSES CRITICS. Invisible Children the group that produced the viral "Kony 2012" video, released a response yesterday to some of the criticism the San Diego-based non-profit has received over the past week. WATCH: http://vimeo.com/38344284 And Joe Brettell, an unpaid adviser to the group, recently penned an Op-Ed defending the organization: "It's not surprising that the runaway success of the Stop Kony effort has attracted its share of critics this week. Some have said that the group's focus is too narrow, while others have questioned their financial stewardship. To be clear, Invisible Children has always been completely transparent - even go so far as to publish five years worth of their audited financial returns online. Moreover, regardless of whether Joseph Kony is in Uganda, the Congo or has fled elsewhere, his presence remains a threat to the African continent. More importantly, those who have been tortured, raped or murdered by his armies deserve justice."  http://fxn.ws/wwzIU1

-TOP DEMOCRAT TAKES PRE-EMPTIVE STRIKE AT GOP BUDGET. "This Republican Congress of Chronic Chaos is dusting off last year's same failed playbook - where seniors would lose their Medicare while Republicans give more tax breaks to millionaires and Big Oil companies," writes Democratic Congressional Campaign Committee Chairman Steve Israel. "I have one response: Bring it on. Tone-deaf House Republicans are preparing a budget that will - again - protect millionaires over Medicare. As with their last budget, House Republicans are giving Americans a window into their souls. And the American people don't like what they're seeing: Republicans' relentless, reckless promise to protect the ultrawealthy at the expense of the middle class and seniors. Republicans might stand for those failed priorities, but middle-class families and seniors won't. Medicare is a sacred bond with seniors that cannot be broken."  Read more:  http://politi.co/ypFUxb

-MOVE ON ATTACKS GOP'S 'WAR' ON WOMEN.  MoveOn.org released a new one-minute television ad today called "GOP War on Women." The ad features female MoveO.org members reciting quotes from Republican leaders such as Presidential nominee Rick Santorum and Rush Limbaugh. It ends with MoveOn.org members saying: "Judging from their comments, the GOP must have a serious problem with women. And until the Republicans get over their issues, we women have got a serious problem with the Republican Party." The spot will run on national cable. WATCH:  http://bit.ly/z3jW2P

 

WHO'S TWEETING?

@tymatsdorf : Hey @JHoganGidley tmrw Mitt is campaigning w/ a lobbyist at a place that took earmarks. C'mon dude, that's a layup

@TheFix : 69% of registered voters think super PACs should be illegal, according to new WaPo/ABC poll.  ow.ly/9CFwo

@jonward11 : 1 thing Romney supporters in Miss. are sweating: it's spring break 4 high school, so higher income fams r out of town  huff.to/xA3NKP

@scottwongDC : Marco Rubio adviser: "We are getting a proctological exam on a daily basis"  politi.co/w2rp2F

@DavidMDrucker : Major GOP donors waiting 4 prez primary 2 conclude,likely 2 focus $$ on House/Senate races if Romney not the nom: bit.ly/xXcfig

 

POLITICAL RADAR

-Mitt Romney will spend the day in Missouri holding a grassroots event with Senator Jim Talent in St. Louis. Romney and Talent will also make an evening stop in Liberty, MO. Matt Romney is on the trail for his father in Honolulu, Hawaii holding a Meet & Greet with the Hawaii Republican Party.

-Rick Santorum will spend Primary Night in Lafayette, Louisiana speaking at the Hilton Hotel. Elizabeth Santorum won't be on the trail with her father, but campaigns for him in Honolulu Hawaii on Caucus Day.

-Newt Gingrich will campaign in Birmingham, Alabama visiting the Birmingham Zoo and addressing a local Chamber of Commerce. The Gingrich Campaign will gather in the evening at Birmingham's Wynfrey Hotel. Callista Gingrich will hold one event on behalf of her husband at the UAV Breast Health Center in Birmingham, AL.

ABC's Josh Haskell (@HaskellBuzz)

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

 

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