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Tomorrow, Super Tuesday is the biggest voting day of the 2016 primary season, and Donald Trump's rivals are desperately trying to throw him off course. Many believe it could be the last chance for either Marco Rubio or Ted Cruz to emerge as a real challenger to Trump. The odds are not in their favor. Even as Trump grapples with the controversy around support he's gotten from white supremacists. NPR's Sarah McCammon has been following his campaign and has this report.
SARAH MCCAMMON, BYLINE: Donald Trump has been under fire since Sunday morning when CNN's Jake Tapper asked him if he'd disavow the support of former KKK leader David Duke and white supremacist groups. The billionaire businessman demurred. This morning on NBC, Trump said he hadn't heard the question.
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DONALD TRUMP: OK, so let me tell you. I'm sitting in a house in Florida with a very bad earpiece that they gave me, and you can hardly hear what he was saying. But what I heard was various groups - and I don't mind disavowing anybody, and I disavow David Duke, and I disavowed him the day before at a major news conference.
MCCAMMON: That didn't satisfy Rival Marco Rubio. In Alcoa, Tenn., today, the Florida senator called Trump unelectable and bad for the party.
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MARCO RUBIO: I don't care how bad the earpiece is. Ku Klux Klan comes through pretty clearly. How can someone like that be our nominee? How can the nominee of the Republican Party, of the party of Lincoln, the party of Reagan, the party of hope and the party of optimism nominate someone who refuses to criticize the Ku Klux Klan or distance themself from an avowed racist like David Duke?
MCCAMMON: Trump is also facing attacks from Texas Senator Ted Cruz, who's hoping to win big in his home state and pick up delegates in other Southern states tomorrow.
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TED CRUZ: You know, it's easy to talk about making America great again. You could even print that on a baseball cap. But the critical question is, do you understand the principles and values that made America great in the first place?
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MCCAMMON: Campaigning in Dallas, Cruz questioned Trump's conservative credentials on gun rights and immigration. He criticized Trump for hiring hundreds of low-wage foreign workers to staff his Mar-a-Lago resort in Florida.
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CRUZ: You don't get to abuse and take advantage of American workers and then suddenly style yourself a champion for American workers.
MCCAMMON: Meanwhile, some other leading Republicans are going after Trump. Nebraska Senator Ben Sasse says he won't vote for Trump even if he's the party's nominee. Former Massachusetts Governor Mitt Romney lashed out at Trump on twitter, calling his response to the KKK questions disgusting and disqualifying. But while campaigning in Virginia today, Trump mostly ignored the attacks. During a large rally, he brushed off several disruptions from protesters chanting black lives matter.
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TRUMP: Get out of here. Get them out. Get them out.
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MCCAMMON: For his supporters, Trump had nothing but affection.
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TRUMP: Thank you very much. I love you. I love you. Get out, and vote; vote; vote; vote.
MCCAMMON: It will be up to voters, many in Super Tuesday states tomorrow, whether to disqualify Trump or send him on his way to the nomination. Sarah McCammon, NPR News. Transcript provided by NPR, Copyright NPR.