Remember the scene in Back to the Future Part II where Marty visits the Biff Tannen Museum and watches Biff on the screen? Here are the parts that were left on the cutting room floor. Does Biff remind you of Trump? Duh, says Bob Gale, writer of Back to the Future II. From a 2015 Daily Beast article:
"We thought about it when we made the movie! Are you kidding?" he says. "You watch Part II again and there's a scene where Marty confronts Biff in his office and there's a huge portrait of Biff on the wall behind Biff, and there's one moment where Biff kind of stands up and he takes exactly the same pose as the portrait? Yeah."
Of course, in the movie, Biff uses the profits from his 27-story casino (the Trump Plaza Hotel, completed in 1984, is 37 floors, by the way) to help shake up the Republican Party, before eventually assuming political power himself, helping transform Hill Valley, California, into a lawless, dystopian wasteland, where hooliganism reigns, dissent is quashed, and wherein Biff encourages every citizen to call him "America's greatest living folk hero."
"Yeah," says Gale. "That's what we were thinking about."