Did the Ground Game Matter in 2012?

John Sides: “Yes, but to an extent far smaller than Obama’s winning margin. Other things equal, Obama’s vote share was about three-tenths of a point higher in counties where Obama had one field office and six-tenths of a point higher in counties where Obama had two or more field offices. (With relatively few counties having more than 2 offices, we did not try to estimate the effect of additional field offices beyond 2.) Romney’s field offices, by contrast, had an effect that was only half this size and could not be estimated with as much statistical confidence. This is consistent with the impression that Obama’s field operation was more effective than Romney’s. Essentially, our best guess is that Romney would have needed two offices in a county to match the effects of one of Obama’s offices, all else equal.”