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

MITT ROMNEY ABC News' Jonathan Karl: "Top GOP Senator Says, 'If Romney Loses Michigan, We Need a New Candidate'" A  prominent Republican senator just told me that if Romney can't win in Michigan, the Republican Party needs to go back to the drawing board and convince somebody new to get into the race. "If Romney cannot win Michigan, we need a new candidate," said the senator, who has not endorsed anyone and requested anonymity. LINK

The Washington Times' Stephen Dinan: " Romney shows trouble keeping supporters from 2008" Mitt Romney's second go-round at a presidential run is not going so well. Nine states have voted so far, and in six of them the former Massachusetts governor has shed supporters who voted for him in 2008, winning fewer votes in each of those states than he did last time. LINK

USA Today's Susan Page: " Home sweet home? Michigan primary a challenge for Romney" Welcome home, Mitt Romney. Not everyone is glad to see you. The state where Romney has his deepest roots - where he was born at Harper Hospital in Detroit, met his future wife while attending high school in suburban Bloomfield Hills, saw his dad elected and re-elected governor - now looms as the unlikely challenge that threatens to upend his path to the Republican presidential nomination. LINK

RICK SANTORUM The New York Times' Trip Gabriel: " Santorum Defends Remarks on Obama and Government's Role in Education" As Rick Santorum has addressed huge, supportive crowds in recent days - with hundreds whooping at his jokes and cheering his blistering criticism of the Obama administration - he seems to be displaying a newfound swagger and letting loose with free-swinging remarks. LINK

The Washington Post's David Fahrenthold and Felicia Sonmez: " In Weaving faith into campaign, Santorum resorts to chiding opponents" As his campaign surges, Rick Santorum is testing an untested model for incorporating religion into his message. He is betting that Americans want a president who uses faith not just to inspire - but also to judge. LINK

Bloomberg's David Lerman: " Santorum Says Obama 'Elevates the Earth Above Man'" Republican presidential candidate Rick Santorum says President Barack Obama is beholden to "radical environmentalists" and has "a world view that elevates the earth above man."  Santorum, who has emerged as the main challenger to former Massachusetts Governor Mitt Romney in the Republican race, sought over the weekend to explain his statement that Obama practices "a different theology" that is "not a theology based on the Bible." LINK

The Los Angeles Times' Mitchell Landsberg and Melanie Mason: " Santorum defends remarks on Obama's faith" Republican presidential candidate Rick Santorum denied Sunday that he had questioned President Obama's Christian faith, but said the president held an environmental belief "that elevates the Earth above man." Santorum was quoted Saturday as telling an audience in Ohio that although he accepted the president's Christianity, he believed Obama adhered to "some phony theology. LINK

NEWT GINGRICH Politico's Ginger Gibson: " Newt Gingrich 2012: Looking south for comeback" Since his loss in Florida, Newt Gingrich has all but disappeared. In Nevada, he essentially flouted public events. He then ignored the next contests in Colorado, Minnesota and Missouri, instead making a few Ohio appearances. LINK

SUPER PAC The New York Daily News' Jonathan Lemire: " Super PAC to the rescue: Mitt Romney ally readies ad blitz targeting Rick Santorum" Mitt Romney's allies opened a familiar playbook Friday: Unleashing a barrage of ads to pummel a suddenly threatening adversary. The pro-Romney super PAC Restore Our Future reserved $2.5 million in upcoming air time in an attempt to slow the momentum of the suddenly surging Rick Santorum, according to Politico. LINK

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