That is where we fundamentally disagree. A vote cast in earnest is, IMO, never a wasted vote. That is democracy. Democracy is not about casting your vote for who you think will win, it is about casting your vote for the party that you think will best serve your interests.
A vote for "to be determined later" is (again IMO) a wasted vote. TPTB in the Democratic party might pick someone I would never, ever vote for. That is worse than a waste.