PHOENIX, AZ - JULY 18: U.S. Sen. Bernie Sanders (I-VT) addresses hecklers and supporters at the Netroots Nation 2015 Presidential Town Hall in the Phoenix Convention Center July 18, 2015 in Phoenix, Arizona. The Democratic presidential candidate spoke of income inequality and the flaws of the criminal justice system to nearly 2,000 audience members. (Photo by Charlie Leight/Getty Images)