All the gop WH candidates over the last 30 years have had the same position on abortion.
Single women favor democrats. Married women favor republicans. Abortion has dropped in importance to voters. In order for it to become an issue, Democrats like Stephanopolis began challenging republicans during the primaries, out of the blue. First about birth control. The only one who fell for it was Santorum. Democrats dont want to lose the Scotus decision, because then the states would have the right to make their own laws. That doesnt fit in centralize govt control. Neither does the 10th amendment, or religious freedom. Hense 501c3 churches are breaking the law on purpose, so they can go to court and get a ruling. LBJ sponsored the amendment to restrict political speech on 501C3 orgs.

If romney or ryan, rolled on the abortion position, the church go'ers would stay home and they would lose. If your base stays home, it doesnt matter what you pick up in the middle. Democrats dont normally cross over on abortion. They just focus on other issues.