PORTSMOUTH, NH - MAY 27:  Democratic presidential candidate and U.S. Sen. Bernie Sanders (I-VT) finishes greeting supporters following a packed town meeting at the South Church May 27, 2015 in Portsmouth, New Hampshire. Sanders officially declared his candidacy yesterday and will run as a Democrat in the presidential election. He is former Secretary of State Hillary Clinton's first challenger for the Democratic nomination.  (Photo by Win McNamee/Getty Images)