I find it interesting that the platforms of the parties have been allowed to be written in such a purely principled way.
The Republican platform on abortion calls for a total ban in all circumstances, even when the mother would otherwise die (and the child with her). The only way it could be purer would be to call for punishing abortionists as murderers.
The Democratic platform, by contrast, goes so far as to call for free abortions ("regardless of ability to pay") in all circumstances whatsoever, presumably right up to the moment of birth. Not only shall we permit any woman who wishes to kill a perfectly healthy child that is two minutes from birth, we shall require Catholics and Mormons and Muslims to help pay for it. Everyone will contribute to this national sacrament: we will all be accomplices, we will all provide material support for it. It's not clear that any greater purity is possible; I suppose we could endorse infanticide after birth. This weekend I read of a young woman who had killed her child shortly after it was born, and who is now on trial. If she had made up her mind about it just a few days earlier, she would have been entitled to kill the child, and you and I would be required to pay for the procedure.
There is no wide public support for either set of propositions. The actual politicians who are running rarely adhere to these pure positions themselves, and might well not vote for a bill brought before them that attempted to enact these rules. The voters would probably punish anyone who actually attempted to enact either set of rules.