In the first presidential election since the Citizens United case transformed the campaign finance landscape, the number of ads airing in the presidential race alone surpassed one million by late October. While 2012 saw a sharp increase in the number of outside interest group players in the election, and corresponding increases in the amount of spending from groups who do not have to disclose their donors, there remained one consistent source of transparency in advertising—the Wesleyan Media Project. A political ad tracking project headed by Assistant Professor of Government Erika Franklin Fowler and colleagues at Bowdoin College and Washington State…