While a few members of the GOP establishment (e.g., the Bush family; Mitt Romney) have conspicuously refused to endorse Trump, the predominant opinion appears to be that Trump is not a real Republican, but a kind of independent and unaccountable force of nature, like an earthquake or a tornado. He is their ally in the all-important battle against Hillary, so he has their support, but he is not one of them, and they bear no responsibility for him. They are free to criticize him as they see fit and to pursue their own interests and ideology through the campaign.
The obvious rationale for this approach is that it protects the GOP brand–low taxes for the wealthy, “freedom,” etc.–in the likely event that Trump implodes. The logical problem with it, however, is that it ignores the wishes of the large proportion of GOP voters who clearly prefer swaggering government to limited government.
Will moderate swing voters buy into the idea that the GOP is actually Paul Ryan and Mitch McConnell and not Trump and the rank-and-file in congressional and state races? If Trump should somehow prevail in November, will the congressional GOP leadership continue to treat him as an independent, or will the two forces unite? These are extremely important questions, and no one will know the answer until after the election.