Wisconsin has an open primary, meaning the voter does not have to declare party affiliation to vote

[ElsewheresDaughter]

Since McCain has seemingly wrapped up the GOP nomination, I see the potential for mischief among Republicans when Feb. 19 rolls around. They could muddy the Democratic waters by voting (however insincerely) on the Dem side of the ballot. While criticism of the existence of super-delegates is warranted, those party members can offset GOP shenanigans in open primary states. A hundred years ago, there were no primaries. The party bosses chose the candidates without input from the general public.