Denying him the delegates he needs to win -

Which will require RUBIO to win Florida and Kasich to win Ohio... both considered long-shots by me, although Rubio MIGHT win Florida, since trying to predict crazy GOP voters' behavior is never an exact science.

Rubio has shown he can win some states (like progressive Minnesota, which will go ultimately to Hillary electorally anyway no mater what Repubs do). Meanwhile, Kasich has not won ANY state yet.