Interesting.
I think it'll be
2008: Romney/Bush V. Hillary/ Richardson
2012: Romney/Bush V. Obama/Webb
2016: Bush/Pence V. Webb/Ritter
2020: Webb/Ritter V. Pence/Pawlenty
The only problem I'd have with that is that that would basically have the executive branch in Republican hands for 20 years in a row (not to mention 20 years of having a Bush in the executive branch). That's an awfully long time to go while not having the public get tired of you or without having a scandal bring you down. The only time in American history when such a long streak has ever been seen is the period of FDR from 1933-1953, and that was just because the same guy was able to get elected over and over and over.
the Governor of South Carolina (whatizzname--Mark San___?).
Sanford.