Bernie Sanders arrives for a press conference with union workers in East Lansing, Michigan, where he discussed the effect of free trade agreements on American workers.
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Republican presidential hopefuls, retired neurosurgeon Ben Carson and real-estate mogul Donald Trump talk about childhood vaccines during the second Republican presidential debate.
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Hillary Clinton waits behind a curtain before a rally at the University of Wisconsin, Milwaukee on Thursday. She continues to struggle to explain her use of a private email server while secretary of state.