1. He will lose because he has failed to unify his party
2. He will lose because everyone can see he doesn't have the proper temperament and preparedness to be president
3. He will lose because his campaign strategy is beyond stupid (campaigning in Connecticut?)
4. He will lose because Clinton is flooding the airwaves with ads and he isn't responding
5. He will lose because his ground game is almost nonexistent and Clinton's is robust
6. He will lose because he wallows around in ignorance, hate and nonstop lies which are easily refuted
7. He will lose because his ego is so oversized he won't adjust when necessary
8. He will lose because he has no message discipline
9. He will lose because of the demographics he has alienated
10. He will lose because he is a loser
All of these plus the fact that he scared most reasonable Americans into going to the polls just to vote against him.