President Obama and Hillary Clinton walk off Air Force One in Charlotte, N.C., to attend a Clinton campaign event. The costs of that flight will be repaid by the Democratic National Committee.
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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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