States have no right to alienate unalienable rights.
True, but "liberty" is another of those rights, and for 89 years after the Declaration of Independence nearly half of the states OK'd slavery.
Even if we had one more pro-life justice on the Supreme Court, I wouldn't count on the Court sweeping away the last 35 years' worth of rulings, and even if they did, activist lawyers at lower levels would try to render their decision as meaningless as possible. There would be more hope if it was left to the states, so some states could go back to strict restrictions...just as some states were able to end slavery within their borders before 1861. It's not ideal, but the best that might be achievable given the present strength of the pro-death forces.
If Barack wins, even before there are any Supreme Court vacancies, he'll be trying to sweep away any state restrictions on abortion on demand all the time, including partial birth abortion, and sweeping away protections for babies who survive an abortion. That's his track record.