I don't believe that's possible due to privacy concerns. If you wanted to see, you'd have to link to an external site.
Of course, you could have people post below the poll "voted" if they voted but there's no way to force them to put their name down.
Ok. I told people to say "voted", but only some are.
You could always do an informal poll, by taking away the poll tag and telling users to put their name under a section (approve/disapprove), I know that's what the Avatar wiki does.