President Obama departing Air Force One at O'hare International Airport in Chicago on April 2, 2014.
A Donald Trump supporter holds up a campaign sign before it was announced that Donald Trump's, the Republican presidential candidate, rally would be postponed due to "safety concerns" at the University of Illinois Chicago Pavilion on March 11, 2016.
Democratic presidential candidate Hillary Clinton speaks at the Get-Out-The-Vote event on Feb. 17, 2016, at the Parkway Ballroom on Chicago's South Side.
Former President Bill Clinton waves as he leaves Beth Emet The Free Synagogue in Evanston after he campaigns for his wife, Democratic presidential candidate Hillary Clinton, on March 8, 2016.
Vermont Sen. Bernie Sanders speaks at the 'A Future To Believe In' rally on Feb. 25, 2016, during a stop on his Democratic presidential campaign at the Emil and Patricia Jones Convention Center at Chicago State University.
A graduate wears a cap that says "I Am Black Excellence" during the graduation for King College Prep at which first lady Michelle Obama gave a commencement speech on June 9, 2015.
First lady Michelle Obama delivers the commencement speech during Dr. Martin Luther King Jr. College Prep High School graduation ceremony at Chicago State University on June 9, 2015.