The fault lies with the GOP and the failure to reach a consensus on policy despite having 7 years to do so. They acted like the dog who caught the car and didn’t know what to do with it.
The GOP is most comfortable and experienced in the institutional role of "minority party." It's not just that it doesn't know what to do with a majority, it does not want or mean to put into effect what it claims to stand for.
The function of the GOP is to create the illusion of opposition to government control. Without that illusion, the people realize that the vote doesn't matter in the long run.