At Ten Miles Square today, we feature the latest in the ongoing debate (if you can call it that, since the two sides don’t actually talk to each other that much) between political scientists and political journalists about the effects of “campaigning” versus “fundamentals” in explaining the 2012 election results, in a post by influential Monkey Cage founder John Sides about some research he did with Lynn Vavreck for their upcoming book, The Gamble: Choice and Chance In the 2012 Presidential Election. This is a long excerpt, but worth the trouble:
Lynn and I were able to do something that, to our knowledge, has not been done before: estimate the effects of advertising and the ground game simultaneously. We took Dave Leip’s county-level data on Obama and Romney’s vote share and combined it with two measures of campaign activity. First, we relied on advertising data that we and John Geer purchased from the Nielsen Company. These data are measured in gross rating points (GRPs), which help to capture not only the total number of ads but also their likely reach. Second, we relied on the location of Obama and Romney’s field offices. Thus, for each county, we know how many GRPs were purchased at any point before the election and we know something about the extent of the ground game. Our approach allows us to look at the effects of ads and GRPs simultaneously. In our statistical model, we accounted for other features of these counties—including how well Obama did there in 2008 and various demographic characteristics.
Did the ads matter?
Yes, but in very circumscribed ways. The larger the advertising advantage that either candidate had, the more vote share he received. However, the effect of ads appeared to decay quickly. Ads on the day before the election appeared to produce small but measurable gains in vote share. The largest advantage that Obama had in any one county—the equivalent of an additional 300 GRPs on the Monday before Election Day, relative to Romney’s advertising—translated into an additional three-tenths of a point of vote share. The largest advantage that Romney had on the same day—the equivalent of 900 GRPS—translated into almost an additional point of vote share. Romney aired much more advertising than Obama in this last day of the race, so any advertising effect would tend to benefit him overall.
But ads aired before that Monday—even the calendar week before the week of the election—had a much smaller association with vote share. This is consistent with what Michael Franz noted and what previous studies have found: the apparent effects of ads simply do not last long. At one point, Obama advisor David Axelrod argued that early advertising was more important than late advertising, suggesting that Romney’s ad blitz, “back-loading,” was wrongheaded. Axelrod said: “By September, people are disregarding ads. They back-loaded. We front-loaded.” We find that back-loading—airing ads close to the election—was actually more effective than front-loading—airing ads early in the campaign—if the goal was to influence voters on Election Day.
Another thing constrained the effects of ads: it was hard to get a large advertising advantage. The 900-GRP advantage that was Romney’s largest was exceedingly rare close to the election. In fact, despite his late ad blitz, he had a 300-GRP advantage (or more) in only 15% of battleground state counties.
Did the ground game matter?
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….
We simulated a counterfactual in which Obama had no field offices but nothing else changed. In that scenario, we estimate that he would have lost about 248,000 votes nationwide. Given where those votes were located, we estimate that Obama would have lost Florida by a very narrow margin in this scenario. This estimate parallels estimates from the 2008 election. Joshua Darr, Luke Keele, and Matthew Levendusky have estimated that Obama’s 2008 field operation won him about 275,000 votes in total and could have been responsible for his victory in North Carolina. A similar analysis by political scientist Seth Masket found that Obama’s 2008 field operation may have been consequential in North Carolina, Florida, and Indiana.
Thus, Obama appeared to have an advantage on the ground, but not necessarily an advantage large enough to change many outcomes.
Bottom line: you have to have an air and ground game, and you might as well make them as large and efficient as is possible. But assuming a relatively equivalent deployment of paid resources, none of them are going to be decisive in anything other than the closest race. Real life circumstances and partisan affiliations matter more.
