On the other hand, it could have been a way for the GOP to segue from the "bigot party" into a group with reasonable beliefs. Parties change over time, and this could have been a good first step in the right direction.
They're stuck in a local maximum. They can't throw their white, middle-aged religious base (40% of the population or so) under the bus in order to pick up a few extra points from young people who, if they've been paying attention, won't trust GOP pols anyways.
They don't have to throw them under the bus all at once. A significant portion of the GOP's support base is going to be dying over the next few decades.