CBS News Des Moines Democratic Debate
Democratic presidential candidates Bernie Sanders, Hillary Clinton and Martin O'Malley begin their second debate with opening statements and questions domina...
John Dickerson is a CBS senior national correspondent and Chief Political Analyst. He is also a Contributing Writer to The Atlantic and is co-host of the Slate Political Gabfest.
Democratic presidential candidates Bernie Sanders, Hillary Clinton and Martin O'Malley begin their second debate with opening statements and questions domina...