According to Falstaff (http://falstaff-falstaff.blogspot.com/2008/09/defensive-assignments.html):
Okay, I think I've got the Republican defensive game plan down now.
Palin, you're covering Obama.
McCain, you're going after Bush.
Don't worry about Biden -- he'll be occupied talking to himself in the backfield.
If they bring in Hillary to call some plays, just stand aside. Every first down she gets will just demoralize their bench and fans, thinking about who could've been their starting quarterback.