Trump's nightmare? Crowded 2020 primary may cost him the WH

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Studies show people often recoil from 'too many choices,' which has many pundits predicting doom for the Democrats 'large primary' in 2020 – but history offers clues for why the 2020 primary could actually be bad for Pres. Trump. This special report dives into the science and the political history that could shed light on the kind of opponent Trump will face in 2020.