This is it! This is the answer. It says here . . . that Bernie Sanders loves Back to the Future.
October 21st, 2015 is the date that Doc Brown and Marty McFly time traveled to in Back to the Future II. To honor the popular film, Jimmy Kimmel invited the two major stars of the movie franchise to appear on a segment. In the trilogy, Michael J. Fox portrayed Marty McFly while Christopher Lloyd played the iconic role of Dr. Emmett Brown. Both Fox and Lloyd reprised their roles on Kimmel and, in proper style, arrived in a DeLorean. In the hilarious clip, the two are shocked to learn about things like cronuts and smartphones. Oh, how the world has changed!
Senator Bernie Sanders also hung out with Doc Brown in celebration of Back to the Future Day, and the politician couldn't help but tweet about his exciting encounter. Lloyd appeared to be in great spirits as he posed beside the Democratic presidential candidate. The unlikely duo crossed paths when they both arrived to film separate segments of Jimmy Kimmel Live.