The Environment? Who Cares?
Now, as many of the commenters to Yglesias's post point out, it's not really a valid comparison, is it, since gay marriage and abortion are pretty much either/or propositions. "The environment" by contrast, is large, nebulous, abstract. It's not an issue you can be for or against. It's everything. So, the way the poll is phrased, it's a little like asking people whether they would or wouldn't vote for a candidate who disagreed with them about, say, "the universe." Ask them which is more important, gay marriage or the availability of potable water, and I'm sure you'll get a different result.
I don't blame the pollsters entirely, since we have made a habit of framing things this way, as either pro- or anti-environment. That may work fine as shorthand but it doesn't do much for intelligent debate. On the other hand, try discussing the environment without using the word. I'm not sure it can be done. As Gil Scott-Heron put it: Semantics is always a bitch.