Democratic presidential candidates Sen. Bernie Sanders, I-Vt., and Hillary Clinton in Des Moines, Iowa.
Democratic presidential candidates Sen. Bernie Sanders, I-Vt., and Hillary Clinton in Des Moines, Iowa. Evan Vucci, Jacquelyn Martin AP
Democratic presidential candidates Sen. Bernie Sanders, I-Vt., and Hillary Clinton in Des Moines, Iowa. Evan Vucci, Jacquelyn Martin AP