CHAMPAIGN, IL -  MARCH 12: Supporters listen as Democratic presidential candidate U.S. Sen. Bernie Sanders (D-VT) speaks in the Activities and Recreation Center on the campus of the University of Illinois at Urbana-Champaign on March 12, 2016 in Champaign, Illinois. Both Republican and Democratic presidential candidates have been making appearances at events across Illinois to build support in advance of Tuesday's Illinois primary.  (Photo by Charles Ledford/Getty Images)