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

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' Matthew Jaffe and Shushannah Walshe: " Rick Santorum Defends Call for Puerto Rico to Adopt English After Delegate Defection" Rick Santorum Wednesday became the first Republican presidential hopeful in this election to visit Puerto Rico before the island commonwealth's Sunday primary, taking a controversial stand on statehood that he was forced to defend this morning after losing a key supporter. Rather than boost his standing, the trip has ignited a firestorm with Santorum's comment that English would have to be "the main language" in order for Puerto Rico to become a U.S. state. LINK

The Washington Post's Nia-Malika Henderson: " Santorum becomes a leading conservative  voice through campaign's resurrection" Four short months ago, Rick Santorum had hardly registered in national Republican presidential polls or made a blip in the candidate debates. People routinely asked whether he would drop out out of the race. Undaunted, he would reply that he was running the "Little Engine That Could" campaign. LINK

Politico's Maggie Haberman: " Santorum claims he was misquoted on English-in-Puerto Rico comment" Rick Santorum, who was quoted saying English as the "main language" In Puerto Rico had to be a requirement for achieving statehood, ran from that earlier today and insisted he was misquoted, via the AP's Kasie Hunt.  LINK

MITT ROMNEY The Wall Street Journal's Douglas Belkin and Elizabeth Williamson: " Romney Ramps Up Illinois Spending" Mitt Romney has been favored to win in Illinois, thanks to his large financial advantage and a voter pool full of the sort of upper-income, educated Republicans who have backed him in prior contests. But the GOP presidential race is neck and neck ahead of Tuesday's primary, so Mr. Romney scheduled a visit to the state Friday, days earlier than expected, and his campaign and allies are making large advertising buys. LINK

PRESIDENT OBAMA The Hill's Sam Baker: " Obama shifts healthcare defense" The Obama administration has shifted its legal arguments as it prepares to defend the president's healthcare law before the Supreme Court.  LINK   

The New York Daily News' Alison Gendar: " President Obama takes not-so-subtle shots at his Republican rivals, calls them 'Flat Earth Society'" A feisty President Obama likened Republican foes of his energy policies to members of the "Flat Earth Society" who will wind up on the wrong side of history. Obama said he's boosted American oil production to an eight year high, but insisted all the drilling in the world won't get around the fact that the U.S. consumes 20% of the world's oil - but has only 2% of the oil reserves. LINK

VOTERS The New York Times' Kirk Johnson: " G.O.P. Strategy for Hispanic Voters: It's the Economy" For many years, and multiple election cycles, Republicans talked about the growing Hispanic vote in America like moonstruck, misunderstood boys at a high school dance. They could not connect, despite believing that they shared much in common, especially with socially conservative, religious Hispanic voters who would one day realize how charming Republicans could be. LINK 

The Los Angeles Times' Meave Reston: " Republican candidates face big Latino problem" Reporting from San Juan, Puerto Rico- When Mitt Romney heads to Puerto Rico on Friday on the hunt for delegates before Sunday's primary, his campaign hopes to telegraph his message not just to American voters of Puerto Rican descent but to the broader universe of Latinos, who will play an outsized role in November. LINK

OTHER The Washington Times' Andrea Billups: " 'Joe the Plumber' takes the plunge into politics" He is a burly, outspoken, working man's icon, plucked from obscurity during the 2008 presidential election cycle when he was lauded by Republicans for taking on candidate Barack Obama. LINK

ABC NEWS VIDEOS " Obama Blasts Resistance to 'Green' Energy" LINK   

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