One thing that I forgot to mention when I posted before about this: In the U.S. at least, the issues are strongly linked. People's opinions on them are strongly correlated. That's because an authoritarian is going to be authoritarian on everything, typically.
So a 1-dimensional issue-space isn't a bad approximation. With that reasonable approximation, the CW is the SU maximizer. Mike Ossipoff ---- election-methods mailing list - see http://electorama.com/em for list info
