I don’t think anyone’s seriously considered abortion a 50:50 issue in a long time. As far as I remember, it’s always been an extremist faction within the GOP, but a faction large and energized enough to dominate party politics. And it’s been ‘safe’ enough for mainstream GOP to play along with, because it was settled law protected by SCOTUS. Now that protection is gone, GOP politicians are going to have to decide whether courting those extremists in the primaries is worth the cost in the general.