Did you see his debate with Norm Coleman earlier? Someone gave Wellstone Al Gore's playbook from the first Presidential debate in 2000 with Jim Lehrer as moderator. Coleman happily remained affable, civil, concise and informative while Wellstone cut his throat with bullying and hogging and generally running off at the mouth.
Assuming Minnesotans are salt of the earth people with common sense, I can't see them buying this guy for much longer, especially with his voting not to do anything about Saddam in Iraq and his history of gutting our national defense and support technology and weapons for our service members in harm's way.