Chasing one’s tail
Today I heard on the news that President Bush doesn’t like pay much attention to public opinion polls, since it’s like “a dog chasing it’s tail.”
I’d consider chasing after a 1% slip in the polls chasing your tail. But drastically falling numbers would tend to indicate something worth pursuing.
In general, I empathize with the lack of faith in public opinion polls (more to come on that topic later), but when all the random samples start to indicate a plummet in approval, I don’t think the meaning is very ambiguous.