Yeah. Because Obama certainly has an overwhelming advantage here, doesn't he?
That's not the point. Historically, presidential nominees have always choose someone opposite. Governor Clinton chose Senator Gore. Governor Bush chose (former) Representative Cheney.
Sorry, but McCain needs to choose a Governor here. The best options for McCain are Mike Rounds of SD or Sarah Palin of AK. Hopefully he doesn't pick Romney but I'll still hold my nose if he does.