SAN FRANCISCO, CA - JUNE 06: Bernie Sanders speaks at his A future to believe in San Francisco GOTV Concert at Crissy Field San Francisco on June 6, 2016 in San Francisco, California. (Photo by Tim Mosenfelder/Getty Images)
SAN FRANCISCO, CA - JUNE 06: Bernie Sanders speaks at his A future to believe in San Francisco GOTV Concert at Crissy Field San Francisco on June 6, 2016 in San Francisco, California. (Photo by Tim Mosenfelder/Getty Images)