Hillary on the trail

Hillary Clinton speaks during a campaign stop at Beech Hill Farm in Hopkinton, New Hampshire July 28, 2015. REUTERS/Brian Snyder

Hillary Clinton poses for a photo with a supporter after a rally at Trident Technical College Conference Center in North Charleston, South Carolina June 17, 2015. REUTERS/Randall Hill

Hillary Clinton picks out fresh corn during a visit to Dimond Hill Farm in Hopkinton, New Hampshire July 28, 2015. REUTERS/Brian Snyder

Hillary Clinton reacts after a supporter kissed her hand during a campaign stop in a back yard of a home in Windham, New Hampshire July 16, 2015. REUTERS/Brian Snyder

Hillary Clinton looks around a post to greet audience members at a campaign launch party at Carter Hill Orchard in Concord, New Hampshire June 15, 2015. REUTERS/Brian Snyder

Hillary Clinton is seen silhouetted through a U.S. flag at a campaign event in Des Moines, Iowa, June 14, 2015. REUTERS/Jim Young

Hillary Clinton cracks a smile while waiting be introduced by Jan Bauer, the Democratic county chair of Story County, before she speaks at an organizing event at the Reiman Ballroom at the Iowa State University Alumni Center in Ames, Iowa July 26, 2015. The event took place on the 25th anniversary of the passage of the Americans with Disabilities Act. REUTERS/Brian C. Frank

Hillary Clinton adjusts her make-up before speaking at the Iowa Democratic Party's Hall of Fame dinner in Cedar Rapids, Iowa, July 17, 2015. REUTERS/Jim Young

Hillary Clinton reacts as she arrives to give her "official launch speech" at a campaign kick-off rally in Franklin D. Roosevelt Four Freedoms Park on Roosevelt Island in New York, June 13, 2015. REUTERS/Lucas Jackso

Hillary Clinton reads a book to a Pre-K class during a campaign stop at the YMCA in Rochester, New Hampshire June 15, 2015. REUTERS/Brian Snyder

Hillary Clinton greets audience members at a campaign launch party in Concord, New Hampshire June 15, 2015. REUTERS/Brian Snyder

Supporters hold signs before a campaign town hall meeting with Hillary Clinton in Dover, New Hampshire July 16, 2015. REUTERS/Brian Snyder

Hillary Clinton answers questions from reporters following a campaign town hall meeting in Dover, New Hampshire July 16, 2015. REUTERS/Brian Snyder

Hillary Rodham Clinton tours the geothermal system during a visit to the LEED Platinum certified DART Central Station in Des Moines, Iowa July 27, 2015. REUTERS/Scott Morgan

Hillary Clinton hugs her husband former President Bill Clinton as their daughter Chelsea looks on after Clinton delivered her "official launch speech" at a campaign kick off rally in Franklin D. Roosevelt Four Freedoms Park on Roosevelt Island in New York City, June 13, 2015. REUTERS/Carlo Allegri

Sisters Sophia (L) and Norah Boice of North Charleston play on seats after Hillary Clinton spoke at a rally at Trident Technical College Conference Center in North Charleston, South Carolina, June 17, 2015. REUTERS/Randall Hill

Hillary Clinton listens to her introduction before speaking at the Iowa Democratic Party's Hall of Fame dinner in Cedar Rapids, Iowa, July 17, 2015. REUTERS/Jim Young

Hillary Clinton reacts after speaking at a campaign event in Des Moines, Iowa, June 14, 2015. REUTERS/Jim Young