Kerry is further to the left of Dean, Edwards, Clark, and Lieberman.

Hrmm. It's late and my wrist hurts so I won't be looking it up right now, but my hazy recollection was that at least on some issues (gay rights? Abortion?) Clark was distinctly more liberal than Kerry.

Insert obligatory "politics isn't really a one-dimensional variable, so the concept breaks down if we look at it too hard" acknowledgement here.