Exactly Backwards?

Via Kevin Drum, here is a Pew Poll diagram on the perceived ideology of the Presidential candidates (click to enlarge). What jumps out at me is that the perception of the Republicans is more or less correct, while the perception of the Democrats is way, way off. In fact, if you reversed their order on the ideological spectrum you would get a closer approximation of the truth: Hillary and Bill are moderates, while Obama and Edwards are the more leftward options. What does this say? I think part of the answer is that it's early and the public doesn't know the candidates well, but I also think the Democrats have lost their old ideological structures and are in the midst of finding new ones. No one is quite sure where any one stands because there are no set measuring sticks quite yet.