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Democratic presidential candidate Hillary Rodham Clinton looks on as she is introduced to speak during a campaign stop at Uncle Nancy's Coffee House, Sunday, Sept. 6, 2015, in Newton, Iowa. (AP Photo/Charlie Neibergall)
Democratic presidential candidate, Sen. Bernie Sanders, I-Vt., speaks during a television interview before a town hall meeting, Thursday, Sept. 3, 2015, in Grinnell, Iowa. (AP Photo/Charlie Neibergall)
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U.S. Sen. Bernie Sanders (I-VT) speaks during a campaign rally with democratic presidential nominee former Secretary of State Hillary Clinton at University of New Hampshire on September 28, 2016 in Durham, New Hampshire.
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