Minnesota Senate race may end up in court
Unlike what happened in New Jersey, it's fully legal in Minnesota to replace a candidate as close as 4 days before an election. However, there's a wrinkle: under Minnesota law, any absentee votes for Wellstone already cast will be counted for Wellstone and not credited to whomever the replacement candidate will be (looks like Walter Mondale). If the replacement loses by a smaller margin than the number of absentee ballots for Wellstone, look for this to end up in court.
The Minnesota Secretary of State has issued an explaination of the law.