if it is very close then probably some combo of minority bashing and 'rigged' but if he loses by a large margin, then definitely he (and therefore his supporters) will go after the GOP and prominent Never Trumpers like Romney. If he is losing big you can be sure that the money spigot will slow to a trickle by the end. It will probably be worse than it was for McCain (remember how badly he was doing for money at the end in 2008 he went on SNL and did a skit about it).
This.
Indeed, if Trump loses, this will be why.
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