Donald Trump poses for a selfie with a woman wearing a "Team Trump" T-shirt on stage at the National Federation of Republican Assemblies Presidential Preference Convention in Nashville, Tennessee. Jason Davis/Getty Images hide caption

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After working for Republican presidential candidate Rick Perry, Sam Clovis this week decided to switch sides and be rival Donald Trump's national campaign co-chairman. Shown here in 2014, Clovis ran for a U.S. Senate seat from Iowa. Charlie Neibergall/AP hide caption

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Dallas District Attorney Susan Hawk had missed events and been absent for the past three weeks. Her staff said she was on a long vacation, but she later said she is being treated for depression. Courtesy Stella Chavez/KERA News hide caption

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Rep. Chaka Fattah, D-Pa., arrives at the federal courthouse in Philadelphia earlier this month. Fattah has been indicted on charges he misappropriated hundreds of thousands of dollars of federal, charitable and campaign funds. Matt Rourke/AP hide caption

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President George W. Bush (center) surveys the devastation in New Orleans with (from left to right) Vice Adm. Thad Allen, Louisiana Gov. Kathleen Blanco, Mayor Ray Nagin and Lt. Gen. Russel Honore on Sept. 12, 2005, two weeks after Hurricane Katrina slammed into the Gulf Coast. Jim Watson/AFP/Getty Images hide caption

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Sen. Bernie Sanders in his office in 1981, shortly after becoming mayor of Burlington, Vt. He once said his tenure as a socialist mayor is evidence people are willing to accept radical change. Donna Light/AP hide caption

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Mitt Romney peers over the podium at guests being pointed out by his wife, Ann, during an event at which Donald Trump endorsed Romney in 2012. Ethan Miller/Getty Images hide caption

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Donald Trump (left) arrives to announce his bid to run for president on June 16. Arnold Schwarzenegger (right) appeared on the Tonight Show with Jay Leno and announced he was running for governor of California on Aug. 6, 2003. Kena Betancur/AFP/Getty Images and Kevin Winter/Getty Images hide caption

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Sen. Ted Cruz prays before the start of his Religious Liberty Rally last weekend in Des Moines, Iowa. The event was part of Cruz's push to energize evangelical voters. Scott Olson/Getty Images hide caption

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Donald Trump holds financial documents at his campaign announcement in June. He had said he didn't need donors because he could pay for his campaign himself, but he recently said he'd be open to people "investing" in his campaign. Christopher Gregory/Getty Images hide caption

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Last October, a 15-year-old student and member of the Tulalip Tribes in Washington opened fire at his high school with a gun obtained from his father. The tribe had issued a restraining order against the father, but that information didn't show up in the federal criminal database — so he was able to buy the gun. Ted S. Warren/AP hide caption

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Donald Trump and Fox News are at odds again, after the Republican presidential candidate criticized host Megyn Kelly. "Donald Trump rarely apologizes, although in this case, he should," Fox chief Roger Ailes said. Mark Wallheiser/Getty Images hide caption

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