"The" abortion debate is actually 2 debates.
Could you elucidate on that some.
I don't disagree, I think there are two seperate debates - one of whether or not it should be legal, the other of morality, dividing people into three or four different groups depending on how you count.
Legal/ morally acceptable.
Legal/ morally questionable
illegal/morally reprehensible.
I seriously doubt there is are many supporters of the position illegal/morally acceptable. Though one could subdivide the illegal group into those who are 'pro-life' (also opposing war, euthinasia, and capital punishment), and those who are simply anti-abortion.
Still, it could further be argued that there are even more groupings available as not everyone takes the polar positions of illegal always, or legal always. Probably the rough center ground is 'first trimester' or the health of the mother.
In terms of winning, the anti-abortion side has been fairly successful in exploiting wedge issues to their advantage but does not completely dominate public opinion, so I vote #2.