In this Jan. 25, 2016, photo, Democratic presidential candidate Hillary Clinton speaks during a campaign event at the Knoxville School District Administration Office in Knoxville, Iowa. Battling across Iowa ahead of the first-in-the-country vote on Feb. 1, Clinton and Bernie Sanders are dueling on fertile populist ground: resentment against Wall Street, bailed-out big banks and a financial system seen as rigged. (AP Photo/Mary Altaffer)