Oh, I have no doubt he’s in it to win, at this point....
But I think pride/ego/competitiveness are the *main* motivator, not the only one.
I think your points - and mine- are all valid, except that he might not have all that much to lose, he can make more money pretty easily from what I’ve seen.
It truly is the only thing that makes sense. I was trying to play devil's advocate with this - I keep hearing how Trump is just in it to help Hitlery. I reject that for many reasons, but figure, ok, let's just say that IS the case - what does he get out of it? Because he wouldn't do it just for the fun of it. There has to be some reward for him in it, and thus far, even the most rabid anti-Trumpers out there can't answer the question! Says a lot, if you ask me.