It relies on affluent suburbs, according to Michael Barone:
Paul Ryan wins big every year in Waukesha County west of Milwaukee. [Rob] Portman ran well enough in suburbs to carry Ohio's three biggest metro areas in 2010. [Mitch]
Daniels won a higher percentage in Indiana's most affluent area, Hamilton County, than Ronald Reagan did in 1984. And in 2009 [Bob] McDonnell carried Washington's Northern Virginia suburbs, where he grew up, though they had voted heavily for Obama the year before.
A double-vanilla ticket will be attacked as un-diverse by the media. But if the nominees have rapport and energy, as Clinton and Gore did in 1992, who cares? The Clinton-Gore ticket regained Southern ground for Democrats. A double-vanilla ticket might enable Republicans to regain ground in affluent suburbs this year.
(Screenshot from a Colbert segment on Romney veep speculation. A rice cake and a Joseph A. Bank mannequin were also considered.)
The Dish 