Belz...
Fiend God
Sanders is wishfully believing he can end up with more pledged delegates than Clinton resulting in an opening to persuade superdelegates to switch sides.
It's not going to happen but that is where the talk of a brokered Democratic Convention comes from.
Well, no one can blame him for trying. Some have also hoped that Hillary will move to the left to woo his voters once she wins the nomination. Even that would be a win for him, after a fashion.