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, Carrie Halperin and Alicia Tejada

PRESIDENT OBAMA ABC News' Mary Bruce: " Obama Responds to Open-Mic Incident, Jokes 'Are The Mics On?'" President Obama offered his explanation today for the hot-mic moment that caught him asking the Russian president for "flexibility" and "space" on missile defense until after November's election, saying "this is not a matter of hiding the ball." "The only way I get this stuff done is if I'm consulting with the Pentagon, with Congress, if I've got bipartisan support and frankly, the current environment is not conducive to those kinds of thoughtful consultations," Obama told reporters following a meeting with Russian President Dmitri Medvedev and President Nursultan Nazarbayev of Kazakhstan. LINK

The Washington Times' Dave Boyer: " Obama has eye on election at summit"  President Obama pressed Chinese President Hu Jintao to dissuade North Korea from its planned long-range missile launch next month, though Mr. Obama's plea was overshadowed by a few overheard half-whispers that caused a political furor back home over his foreign-policy honesty.   LINK

RON PAUL ABC News' Jason M. Volack: " Ron Paul: 'I Am Trailing but the Race Isn't Over'" Not an interview goes by where Ron Paul isn't asked about the viability of his campaign, and although the Texas congressman usually brushes off the questions by reiterating that he's in it for the long run, Paul got testy when asked why he doesn't just do the "decent thing and pull out" on "Piers Morgan Tonight." "Why don't you do the decent thing and not pester me with silly questions like that," a fiery Paul replied to host Morgan. "I mean that would be decent of you." LINK

RICK SANTORUM The Wall Street Journal's Colleen McCain Nelson and Peter Nicholas: " Santorum Faces Choices on His Next Steps" Rick Santorum has built national name recognition and a large constituency of conservative Republicans during the presidential nominating process. Now, as his hopes dim for claiming the nomination, he faces a choice on how best to build on his political standing. LINK

New York Times' Katharine Q. Seelye: " Santorum Fails to Capture Catholic Vote"  Cathy Willauer, who is Roman Catholic and a mother of four, says that her religion is important to her and that she shares the same values as Rick Santorum.  But Mrs. Willauer, 50, who lives in Annapolis, Md., has decided to support Mitt Romney in Maryland's Republican presidential primary on April 3.  LINK

The Boston Globe's Callum Borchers: " Santorum defends use of profanity in response to reporter" Republican presidential candidate Rick Santorum isn't backing off his use of a swear word directed at a New York Times reporter Sunday night, likening the episode to standing up to a bully. "I criticized Romney and Obama for their outrageous health care legislation," Santorum wrote in an e-mail to supporters.  LINK

The New York Daily News' Alison Gendar: " GOP candidate Rick Santorum says he would join Mitt Romney on ticket if asked"Rick Santorum may be ranting about the potential for Mitt Romney to be an Etch-a-Sketch-in-Chief - but that doesn't mean the conservative wouldn't be his running mate."Of course," the former Pennsylvania Sen. responded when a reporter for the Christian Broadcasting Network asked him Monday what he would say if Romney asked him to join the ticket. LINK

MITT ROMNEY USA Today's Catalina Camia: " Romney slams Obama for open mike comments" Mitt Romney slammed President Obama's comments about having "flexibility" after the general election, saying the remarks captured on an open microphone represent "an alarming and troubling development." Newt Gingrich also weighed in, telling CNN that he believed Obama's remarks were "cynical." LINK

The Los Angeles Times' Maeve Reston and Seema Mehta: " Romney visits California as candidates slam Obama on healthcare" Republican presidential candidates renewed their criticism of President Obama's healthcare program Monday in a double-barreled assault from both coasts. Standing before a "Repeal and Replace Obamacare" banner at a medical device manufacturer in San Diego as he opened a campaign swing in the state, Mitt Romney called the president's policies "an attack on free enterprise, an attack on economic freedom unlike anything we have ever seen before." LINK

Bloomberg's Alex Wayne: " Romneycare's 98% Success Rate Defies Gripes on Obama Law"  The success of the Massachusetts health-care system is spurring President Barack Obama to extol the virtues of a law Mitt Romney signed as a governor.  Romney, running for the Republican presidential nomination, says it shouldn't be the model for every state.  LINK

OTHER Politico's Alex Castellanos: " Hitting reset on the 2012 presidential race"  There is a question keeping President Barack Obama and his talented reelection team up at night: What if Eric Fehrnstrom was right?  Fehrnstrom is the author of Sen. Scott Brown's stunning, come-from-behind victory in 2010 and, perhaps, the most politically astute member of Team Romney.  LINK

The Hill's Josh Lederman: " Republican contenders use High Court hearing to blast president, each other" The Republican presidential contenders seized Monday's Supreme Court hearing as a ready-made opportunity to bash President Obama - and each other.  Rick Santorum, who is struggling to keep momentum in his campaign, made the highest-profile play to capitalize on the first day of arguments, traveling to Washington to appear on the steps of the high court. LINK

The Washington Post's Chris Cillizza: " The "walking dead" phase of the Republican primary is upon us"  This is how primary campaigns end - not with a bang but with a wimper. Or, more accurately, a whine. Rick Santorum lost his temper with the New York Times' Jeff Zeleny on Sunday when Zeleny, perhaps the most even-tempered reporter we know, pushed the former Pennsylvania Senator on his remark that former Massachusetts governor Mitt Romney would be the "worst Republican" to nominate against President Obama .   LINK

ABC NEWS VIDEOS " Santorum Speaks Outside Supreme Court" LINK

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