A security guard for Republican presidential candidate Donald Trump removes Univision anchor Jorge Ramos from a news conference on Tuesday in Iowa. Charlie Neibergall/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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Butler County Sheriff Richard Jones stands next to a illegal aliens sign he had placed in the parking lot of the Butler County Sheriff's Department, Nov. 3, 2005, in Hamilton, Ohio. David Kohl/AP hide caption

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Republican presidential candidate Donald Trump speaks at a press conference Wednesday prior to a town hall meeting at Pinkerton Academy in Derry, N.H. Matthew Healey/UPI/Landov hide caption

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A woman holds signs depicting the head of Republican presidential candidate and businessman Donald Trump as she waits to enter the auditorium to hear him speak on Wednesday in Derry, N.H. Mary Schwalm/AP hide caption

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Donald Trump wears what's become a campaign signature: his "Make America Great Again" hat. Part of making the country great again, Trump says, is implementing his hard-line immigration plan. Scott Heppell/AP hide caption

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Donald Trump continues to lead in the polls and on Sunday released his first policy position — a conservative proposal on immigration. Seth Wenig/AP hide caption

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Sen. Bernie Sanders, I-Vt., has gotten some of the biggest and most devoted crowds of the 2016 presidential race, including in Portland, Ore., this month, where he drew more than 19,000. Troy Wayrynen/AP hide caption

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Republican presidential candidates Donald Trump (right) and Wisconsin Gov. Scott Walker speak together during a commercial break at the first Republican presidential debate in Cleveland on Thursday. Trump's remarks about Fox News debate moderator Megyn Kelly have triggered a firestorm. Andrew Harnik/AP hide caption

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Former Florida Gov. Jeb Bush speaks during the first Republican presidential debate Thursday in Cleveland. Bush touted his jobs record in Florida. Andrew Harnik/AP hide caption

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Republican presidential candidates, from left, Lindsey Graham, Ben Carson, John Kasich, Chris Christie, Bobby Jindal, Jeb Bush, Scott Walker and Rick Santorum speak among themselves after a forum Monday, Aug. 3, 2015, in Manchester, N.H. Jim Cole/AP hide caption

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