If you can't watch the ad above from Karl Rove's Crossroads GPS, this screen capture pretty much tells the whole story:
Yup, the whole ad is about how Tim Kaine is joined at Barack Obama's hip, because apparently Karl Rove still thinks Virginia is like Alabama. But in reality:
Public Policy Polling. 4/26-29. Registered voters. MoE 3.8%
Barack Obama 50
Mitt Romney 38
Indeed, Obama has consistently scored higher marks against Romney than Tim Kaine has against George Allen (essentially a tied race).