This Sunday: Gingrich, Giuliani, Kranish, O'Donnell, Dickerson

This Sunday's Guests are Presidential Candidate Newt Gingrich, Former Mayor of New York City Rudy Giuliani and a roundtable with Michael Kranish, the Boston Globe editor and co-author of The Real Romney, CBS News Chief White House Correspondent Norah O'Donnell and CBS News Political Director John Dickerson.

Viva Las Vegas. That's what former House Speaker Newt Gingrich is hoping to say Sunday after Republicans go to the polls in Nevada. After losing Florida by double digits to Mitt Romney, Gingrich is looking to get back to the winner's circle.

Romney got some possible help from real estate mogul Donald Trump, who just last week told Bob Schieffer he was still thinking about running himself, but this Thursday endorsed Mitt Romney.

"Mitt is tough he's smart he's sharp he's not going to allow bad things to continue to happen to this country that we all love," said Trump in what many in attendance said was an awkward political event.

Romney's campaign has spent the week defending his comments to CNN the morning after his big win in Florida when he said his focus wasn't on the poor, but on the middle class.

"I'm not concerned about the very poor, we have a safety net there. If it needs a repair I'll fix it. I'm not concerned about the very rich, they're doing just fine. I'm concerned about the very heart of America, the 90-95% of Americans who right now are struggling. I'll take that across the nation," said Romney.

Critics pounced, saying it was another instance of Romney showing he was out of touch with mainstream America.

"I really believe that we should care about the very poor, unlike Gov. Romney," said Gingrich. "I'm for replacing the safety net with a trampoline... Nothing is better for somebody who is poor than getting a job and getting a paycheck and having a chance to rise and having their children see that it is OK to go to work and that it is a part of being an American," he said.

In 2008, Former New York City Mayor Rudy Giuliani saw his Presidential aspirations end after a weak showing in Florida. Giuliani recently criticized Gingrich and other Republicans for attacking Romney's record at the private equity firm Bain Capital. "I'm going to say its ignorant, dumb," said Giuliani of the attacks. "It is building something we should be fighting in America: ignorance of the American economic system. Playing on the dumbest, most ridiculous ideas about how you grow jobs," he said in an interview on FOX News.

Michael Kranish of the Boston Globe has raised some eyebrows with his new biography of Mitt Romney, called The Real Romney. In it, Kranish and co-author Scott Helman detail the former Governor's rise, his family's history in the Mormon Church, and his record in private industry, which is the cornerstone of his campaign. "Romney has stood by his assertion that he helped create a 'net, net' of tens of thousands of jobs, and Bain Capital officials said in 2011 that his claim is accurate. However, neither Romney nor Bain provided documentation of that claim. Nor is the claim something that can be verified independently with anything approaching certainty," they wrote.

Can Gingrich bounce back in Nevada even though Romney is leading many polls? Can Romney's momentum be stopped? Will Donald Trump even matter or could his endorsement hurt the current frontrunner? Will Romney's flubs take a toll on his momentum? Those will be among the issues as Candidate Gingrich, one-time Candidate Giuliani and Romney Biographer Michael Kranish and CBS's Norah O'Donnell and John Dickerson join Bob Schieffer to Face the Nation.

Check here for your local listings so you don't miss this week's Face the Nation.