This looks bad right now, but in reality republicans probably saved themselves from a 2018 shellacking by not passing this utterly terrible bill.
By pissing off their own base with keeping the mandate for two more years? This was a lose-lose situation in my opinion.
You are forgetting that most voters don't know anything and those that do only care for 5 minutes. Two years from now nobody will be voting on the basis of the GOP failing to repeal Obamacare, but a lot of people would have voted against the GOP if they had gotten much worse health care, whoch would have been the resukt fir millions with this bill.