LAS VEGAS, NV – FEBRUARY 14: Democratic presidential candidate Hillary Clinton (L) looks on as U.S. Rep. John Lewis (D-GA) speaks on her behalf at a get-out-the-caucus event at the Mountain Shadows Community Center on February 14, 2016 in Las Vegas, Nevada. Clinton is challenging Sen. Bernie Sanders for the Democratic presidential nomination ahead of Nevada’s February 20th Democratic caucus. (Photo by Ethan Miller/Getty Images)

