You forgot one
West Virginia-Special Election. Lets face it Robert Byrd is in bad condition and he may not be around this time next year. Given how WV has shifted to the GOP over the years and with the Filibuster on the line I would say this would be a good pick-up opportunity for the GOP espcially if Shelley Moore Capito(R-WV) runs. Even though I don;t like Byrd that much I think he will be a big loss to the Senate.
The Republicans just got murdered in the state elections in WV (again). And Capito would have some problems appealing to voters outside her district for one or two reasons though, really, most things would depend on the Democratic primary (both in terms of viciousness (Democratic primaries in WV can be really, really nasty) and, of course, of who gets the nod).
Let's just say that her running's a conditio sine qua non if this is supposed to be remotely interesting.