Imagine a Kerry/McCain vs. Bush/Miller (Zell) campaign. Stranger things have happened.
It'd be the "No, WE'RE more bipartisan!" campaign.
Maybe Bush should tell McCain to keep stringing Kerry along. As long as there is hope of McCain, Cheeky's boytoy won't pick anyone else. Just have McCain say he'll think about it...and keep thinking about it until the day after Kerry, without a VP, loses the election.