We may still see some hiccups and occasional spikes in the wrong direction, but the long-term prospects for abortion support look almost as grim as abortion itself.
Adam Serwer clarifies:
[A] large majority—77 percent—of Americans support abortion being legal in all or "certain circumstances," and just 20 percent of Americans are actually "pro-life" in the sense that opponents of legalized abortion understand the term. … That's good news for someone, but not for people who want to outlaw abortion.
The modern [pro-choice] movement largely came into being to defend Roe v. Wade, the 1973 Supreme Court case legalizing abortion. It might be that a label developed 40 years ago might not speak to abortion rights supporters in a way it did for previous generations.
Ed Kilgore, on the other hand, discounts the poll:
The poll is likely an outlier, as the one in 2009 clearly seemed to be, particularly given the unusual stability over time of public opinion on abortion.
I take Kilgore's point about 2009 and about measuring nebulous things like being "pro-choice". But I think it's interesting and salient that public attitudes toward abortion have shifted slightly toward a more pro-life position in the last decade or so, and that this includes the younger generation. There isn't anything like majority support for banning it altogether as the GOP wants – but Americans seem more attuned the to gravity of the moral question here. Compare that with the issue of marriage equality. The only inference is that there are a lot of pro-marriage equality folks who are also anti-abortion. I don't want to criminalize abortion in the first trimester, but if I had to describe myself, I'd probably say "pro-life."