Those ratings are virtually meaningless. The most damage elected official do is not in votes anyway.
Look at Orin Hatch. He supposedly had a good pro-life rating, yet he did more to help abortion than any of the Democrat Senators. He made a deal with the Democrats that all their pro-abortion Supreme Court nominees would be rubber stamped, but any pro-life nominees specifically would have a higher bar.
As the head of the Senate Judiciary Committee from 1995-2005 he deliberately stuffed the courts with rabidly pro-abortion judges. The pro-abortion groups actually laugh at us, because they know what he did for their side and we were supporting him. But go ahead, trumpet, his 0% NARAL rating.
And what will be the rating of a senator who supports late-term abortion?