U.S. Senator Bernie Sanders, an Independent from Vermont and 2016 U.S. presidential candidate, speaks during a campaign rally in Madison, Wisconsin, U.S., on Wednesday, July 1, 2015. Sanders said he had attracted 200,000 donors as of mid-June and his campaign had raised $8.3 million online through June 17, according to FEC filings by ActBlue, the fundraising platform that he and some other left-leaning candidates and causes use. Photographer: Christopher Dilts/Bloomberg via Getty Images