Democratic Presidential Contenders Set To Face Off In First Primary Debates

Twenty presidential contenders will square off in Miami on Wednesday and Thursday for the first Democratic primary debates. Around this time four years ago, a celebrity billionaire ruffled feathers in primary debates, only to eventually beat out every other challenger. Here & Now's Robin Young discusses the impact of primary debates with  Julian Zelizer (@julianzelizer), professor of history and public affairs at Princeton University and a CNN political analyst.