Here is Gallup's summary of attitudes towards abortion. It's clear that abortion is not, at this point, a major issue in this election -- though this is at least partly because most people take their cues on what issues are important from the media and the parties, and no one is campaigning on abortion. It's also notable that people generally support a ban on partial-birth abortions. (Which is understandable. I support all abortions; people who feel like aborting their fetuses eight months in have no business having kids. However, there is obviously a thin line between partial-birth abortion and infanticide.) This is problematic for Obama, who's broadly in favor of killing fetuses.
It still seems like a good idea to use culture-war issues to tie Palin (and the ticket) to Bush -- esp. because there are other issues, like stem cell research, that are substantially less popular than abortion. But it might take a little more care than I assumed. The majorities simply aren't big or firm enough.