Impending demographic changes guarantee this.
But it will take painfully longer than it would naturally occur because of Fox News.
I think of it like this. The GOP, suffering from a horrific traffic accident, is now in the hospital on life support. They are comatose and the life support machine is called Fox News.
Many people in such a dibilitating state, would simply prefer to have the doctor pull the plug, but as long as Murdoch is alive, the Fox News life support machine will keep running. There may come a time when the conservative base will turn on Fox News itself for leading them down this path and forcing them to endure such pain over multiple election cycles.
This will be a long, slow, agonizing death for the GOP because of the Fox life support machine.