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, Jacqueline Fernandez, Amanda VanAllen, and Carrie Halperin

PRESIDENT OBAMA: The Los Angeles Times' Jim Puzzanghera and Kathleen Hennessey: " Obama proposes cutting corporate tax rate to 28% from 35%" President Obama's proposal to lower the corporate tax rate to 28% from 35% shows a growing consensus in Washington that many companies need to pay less in taxes for the U.S. to stay competitive globally.  But exactly how to do that - and which companies should pay more to make up the difference - remains elusive in a volatile election year.  LINK

MITT ROMNEY: ABC News' Matthew Negrin: " Frontrunner Envy? Mitt Romney Claws at Rick Santorum in Debate" The first words out of Mitt Romney's mouth at tonight's Republican debate were a planned attack on Rick Santorum. Time and time again on stage, Romney turned to his right to label Santorum a spender of government money who favored earmarks, not the conservative he has proclaimed himself throughout his campaign. LINK

The New York Times' Jeff Zeleny and Jim Rutenberg: " Romney, Seeking Traction, Duels With Santorum" Mitt Romney challenged Rick Santorum's credentials as a fiscal conservative in a fiercely combative debate on Wednesday, trying to redefine Mr. Santorum as part of the problem in Washington and regain his footing in the fight for the Republican presidential nomination. LINK

The Washington Post's Philip Rucker and Zachary Goldfarb: " Romney, Obama release dueling tax overhaul proposals" Mitt Romney and President Obama released dueling tax overhaul proposals on Wednesday, touching off a fresh election-year debate over the federal deficit and the taxes paid by wealthy individuals and companies. LINK

The Hill's Josh Lederman " Romney, Santorum rip into one another at pivotal GOP debate" Mitt Romney and Rick Santorum ripped into one another at Wednesday night's GOP presidential debate in their last joint appearance before a chain of make-or-break contests.  Romney was helped out in his attacks by his GOP rivals, which left Santorum, who has surged in the polls recently, playing defense most of the night. LINK

RICK SANTORUM: Bloomberg's Lisa Lerer and Kristin Jensen: " Santorum Attacked in Debate on Spending" Rick Santorum and Mitt Romney sparred over spending, federal bailouts and taxes in a debate last night, with the two leading contenders for the Republican presidential nomination competing to define themselves as the race's most authentic conservative.  Romney hammered Santorum for voting as a U.S. senator from Pennsylvania for an Alaska road project that came to symbolize the congressional earmarking process used by lawmakers to funnel tax dollars to pet programs.  LINK

The New York Daily News' " Arizona Republican debate: GOP rivals slam Santorum as Paul labels him a 'fake'" Rick Santorum, viewed as a GOP co-front-runner for the first time, took heat from all sides in Wednesday night's Republican debate - and even had to ward off a charge that he was "a fake." The former Pennsylvania senator traded blows with his main rival, Mitt Romney, but came under fire from Texas Rep. Ron Paul, who answered a question as to why he ran an ad proclaiming Santorum as phony by simply saying "because he's a fake." LINK

The Washington Times' Stephen Dinan: " Rivals target Santorum in debate" The Republican presidential field became a circular firing squad Wednesday night, with the four major candidates accusing each other of failing to live up to conservative principles - with rising candidate Rick Santorum taking the brunt of attacks.  In a debate before a boisterous Arizona audience, most of the candidates backed the state's strict approach to illegal immigration - Mitt Romney went so far as to call it "a model" - and accused President Obama of pushing too far in requiring religiously affiliated institutions, such as Catholic colleges and hospitals, to provide insurance coverage for contraceptives. LINK

USA Today's Susan Page and Jackie Kucinich: " Santorum gets hit from all sides in debate" Nineteen debates later, it was finally Rick Santorum's turn at center stage. His prize: Fire from both sides. Former Massachusetts governor Mitt Romney accused Santorum, the latest leader in national polls, of being a big spender who as a senator from Pennsylvania voted five times to raise the debt ceiling and to approve earmark spending. LINK

The Wall Street Journal's Janet Hook and Patrick O'Connor: " Santorum Draws Fire in Fight for GOP Lead" Republican presidential candidate Mitt Romney sought Wednesday to portray Rick Santorum's 16-year career in Congress as a betrayal of conservative principles, using a televised debate to try to define his top rival at a moment when many voters are paying new attention to the former senator. Mr. Santorum has been on stage for months with the other GOP candidates, but his recent status as national front-runner in the nominating contest is bringing him fresh attention and scrutiny. LINK

NEWT GINGRICH: Politico's Ginger Gibson: " Newt Gingrich is winner for 1 night" Newt Gingrich didn't have a game-changing moment in Wednesday night's Arizona debate. But the former House speaker's newest approach to the Republican presidential race - staying above the fray, avoiding attacks and focusing on the issues - proved to be a winner for him anyway. LINK

ABC NEWS VIDEOS: " Ron Paul Ad's Call Santorum a 'Fake'" LINK " Rick Santorum Defends Earmarks" LINK " Romney: 'If Elected, I Will Repeal 'Obamacare'" LINK

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