Compiled by ABC News' Jayce Henderson, Jacqueline Fernandez and Amanda VanAllen

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

RICK SANTORUM ABC News' Michael Falcone: " Santorum Campaign Invites Democratic Votes In Michigan Robo-Call" How badly does  Rick Santorum want to win Tuesday's Republican primary in Michigan? So badly his campaign is making an appeal to Democrats on primary eve. Santorum, who is locked in a tight race with Mitt Romney here, has paid for robo-calls inviting Democrats to cross-over and vote for him. LINK

The Washington Post: " Rick Santorum takes heat for 'snob' comment against President Obama" Rick Santorum calls it snobbery to suggest that students ought to go to college. On Monday, several of his fellow Republicans - and President Obama - begged to differ. Some GOP governors in Washington for the National Governors Association took issue with Santorum's remark, which he made Saturday as he mounted a last-minute sprint for votes before Tuesday's primary in Michigan. LINK

The Boston Globe's Bobby Caina Calvan: " Santorum makes final appeal for Michigan votes"  Rick Santorum appealed to supporters today for "a game-changing day" in a pivotal election that could further reshape the dynamics of the topsy-turvy contest for the GOP's presidential nomination. "Tomorrow is going to be a big day," Santorum told a packed ballroom at a Lansing hotel. "You have the chance to be the inflection point in this race." LINK

NEWT GINGRICH ABC News' Elicia Dover: " Gingrich, Campaigning in the South, Slams Santorum" Newt Gingrich is spending the next couple of days on his campaign bus traveling from Tennessee to Georgia, trying to appeal for Super Tuesday votes. While Gingrich hasn't gone after Rick Santorum a lot in his stump speeches in the past, today Gingrich hit Santorum, who is leading in the polls in Tennessee. "He has had two weeks of being the alternative," Gingrich said. "The fact is, I think there are profound reasons that Rick lost his Senate race in Pennsylvania history in 2006 and I think it is very hard for him to carry that all the way to the general." LINK

MICHIGAN PRIMARY The New York Daily News' Celeste Katz: " As Mitt Romney and Rick Santorum slug it out in Michigan, President Obama's numbers go up" Mitt Romney and Rick Santorum crisscrossed Michigan Monday in a pre-primary frenzy as polls showed the former Massachusetts governor with a cushy lead in Arizona - and a narrow edge in the Wolverine State. The winner of this to-the-death duel? President Obama. LINK

The New York Times' Jeff Zeleny and Jim Rutenberg: " Michigan a Testing Ground for Doubt on Romney" The Michigan presidential primary on Tuesday offers Rick Santorum - and skeptical conservatives - the best chance yet to turn nagging questions about Mitt Romney into deep doubts about his candidacy. LINK

The Hill's Josh Lederman: " Romney and Santorum hurtle to a photo finish"  Mitt Romney and Rick Santorum blanketed Michigan on Monday, hoping to seal the deal ahead of a neck-and-neck primary that could have enormous implications for the GOP presidential race. But Tuesday's contests in Michigan and Arizona couldn't come soon enough for the Republican candidates, all four of whom emerged bruised and visibly depleted by the most recent stretch of the campaign. LINK

MITT ROMNEY USA Today's Jackie Kucinich: " Romney makes last-minute effort to woo Michigan voters" Mitt Romney barnstormed across his home state Monday with turnout on his mind. Today's Republican presidential primary in Michigan, once expected to be a cakewalk for Romney, has turned into a fierce battle between the former Massachusetts governor and former Pennsylvania senator Rick Santorum. LINK

The Los Angeles Times' Hector Becerra and Mitchell Landsberg: " Romney's at odds with Mormon Church on immigration" Celia Alejandra Alvarez spent three months in a Maricopa County jail after deputies arrested her and other illegal immigrants working at a landscaping business. She said a saving grace during the "90 long days" three years ago were the visits and help she received from her "brothers" and "sisters" with the Church of Jesus Christ of Latter-day Saints. LINK

The Wall Street Journal's Janet Hook and Neil King Jr.: " A Crucial Test for Romney" Michigan's Republican presidential primary Tuesday is more than a test of Mitt Romney's ability to win his native state. It is a test of a central thesis of his campaign: He has the best chance of beating President Barack Obama. The results will show whether Mr. Romney-the longtime GOP front-runner now locked in a close race nationally with former Sen. Rick Santorum-can win the blue-collar voters who are a pivotal bloc in the Midwest, where parties win or lose presidential elections. LINK

The Washington Times' Stephen Dinan: " Arizona set to test Romney's appeal to Hispanics" With this weekend's endorsement by Arizona Gov. Jan Brewer, Mitt Romney has amassed the backing of what could be considered the trifecta of hard-liners on illegal immigration - and he will put that to the test with Hispanic voters Tuesday in Arizona's GOP primary. LINK

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