The Note's Must-Reads are a round-up of today's political headlines and stories from ABC News and the top U.S. newspapers. Posted Monday through Friday right here at www.abcnews.com

Compiled by ABC News' Jayce Henderson, Amanda VanAllen, and Alicia Tejada

PRESIDENT OBAMA: Bloomberg's Mike Dorning: " Obama in Poll Wins More Americans Than Not Saying They're Better" The U.S. public's economic outlook is turning from fear to hope with the presidential election campaign under way. More than twice as many Americans view the economy's prospects as brightening as see them darkening, a reversal from nine months ago, when more people expected deterioration ahead, according to a Bloomberg National Poll conducted March 8-11. LINK

RICK SANTORUM: The New York Times' Jeff Zeleny: " Santorum Wins Alabama and Mississippi Primaries" Rick Santorum captured twin victories in the Alabama and Mississippi primaries on Tuesday, overcoming the financial advantages of Mitt Romney and the Southern allegiances to Newt Gingrich on a night that amplified his argument that the Republican nominating fight is becoming a two-man race with Mr. Romney. LINK

The Washington Post's Dan Balz: " Rick Santorum hoping ideology will trump electability" Ever since he swept three contests on a single night in February, Rick Santorum has argued that the Republican presidential nomination battle is effectively a two-man race between himself and Mitt Romney. LINK

The Washington Times' Seth McLaughlin: " Santorum is a 'David' of his own making" Rick Santorum is casting his fight with Mitt Romney as a "David-versus-Goliath" battle - but from failing to get his name on ballots to coming up short on raising cash, the Republican presidential contender deserves at least part of the blame for his underfunded, underdog campaign, political observers say. LINK

The Hill's Josh Lederman and Justin Sink: " Santorum wins Alabama, Miss.; Romney takes third in both" Rick Santorum swept the Alabama and Mississippi primaries Tuesday night, dealing a blow to front-runner Mitt Romney's campaign and giving weight to his argument that Newt Gingrich should clear the way for a two-way race between Santorum and the former governor.  LINK

Politico's Maggie Haberman: " Alabama and Mississippi primaries: 5 takeaways"  As it turned out, the Mississippi and Alabama presidential primary results were indeed a surprise. Rick Santorum swept the South, Mitt Romney's campaign sought to spin defeat and Newt Gingrich thumbed his nose at the front-runner at the end of yet another Tuesday night in the 2012 battle. LINK

The Wall Street Journal's Patrick O'Connor and Sara Murray: " Wins in South For Santorum" Rick Santorum won the Republican presidential primaries in Alabama and Mississippi Tuesday, solidifying his claim to be the favored candidate of the party's conservative base and the main challenger to front-runner Mitt Romney. Mr. Santorum's victories will bring new clarity to a race so far marked primarily by the inability of Mr. Romney to overcome resistance from the party's most conservative voters. LINK

NEWT GINGRICH: ABC News' Elicia Dover: " Newt Gingrich Says Romney's Inevitability 'Collapsed'" Republican presidential candidate Newt Gingrich lost both Alabama and Mississippi to Rick Santorum Tuesday. But while Gingrich campaign advisers had called the two states "must-win" just last week, more recently he said that no matter what the outcome Tuesday, he would still soldier on to other primaries and all the way to the convention in Tampa. LINK

The Los Angeles Times' John Hoeffel: " Gingrich vows fight, says Romney 'not much of a front-runner'" Newt Gingrich fell short in his bid Tuesday to reignite his presidential campaign with wins in two Southern primaries but did not budge from his pledge to go all the way to the Republican convention, arguing that the results from Alabama and Mississippi undercut Mitt Romney's claim to the nomination. LINK

ABC NEWS VIDEOS: " Gingrich: 'Everything Obama Knows Is Wrong'" LINK " Santorum Wins Alabama" LINK " Gingrich Denies Splitting GOP Votes" LINK

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