This ticket would be an unmitigatged disaster for the Democrats. Ultra liberal Wellstone, who never even kept his word on not seeking another term for the U.S. Senate, would be defeated decisively in this election. His extreme liberalism would frighten many Democrats into voting for Bush, and independents would break overwhelming for Bush.
The Democrats would only salvage the most die hard Democratic states in this election.
Dean does not help at all, a total lightweight.
In short, no contest, a decisive and clear win for Bush and Cheney.
Bush/Cheney 360 EV 58% PV
Wellstone/Dean 178 EV 42% PV