There are any number of ways one could interpret the results of this poll.
If you're cynical, you might conclude that people are liars. If 66% of people (even 57% of conservatives! even 67% of NASCAR fans!) think driving a fuel-efficient car is patriotic, then why aren't they driving fuel-efficient cars? One might conclude that patriotism is a handy way to attack people you dislike, but somewhat hollow as an actual motivation for sacrifice, or even changing one's own behavior.
If you're a more optimistic type, you might conclude that this level of support for fuel efficiency -- 89% think it's important for government to act to reach 40mpg -- is a vast, largely untapped political force. One might think that an aggressive program of education and advocacy would open people's eyes up to the fact that their government is in fact doing very little, and get them fired up.
Or one could just conclude that polls don't mean much at all.
(The full results of the poll are in a press release here as a PDF.)
Also, check out 40mpg.org, launched today in the wake of the poll. Very cool site.