Outside Spending Goes Red

The Wesleyan Media Project reports:

With prognosticators giving even odds that Republicans will take over the U.S. Senate after this November’s elections, outside groups are taking notice. Almost 52 percent of ads aired in favor of Republican candidates have been sponsored by interest groups, and that figure is 40 percent on the Democratic side. Groups have spent an estimated $97 million on advertising in Senate races this election cycle, which is up from the estimated $78 million spent to this point in the 2012 election cycle.
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A Wesleyan Media Project analysis, in partnership with the Center for Responsive Politics, reveals that over half (56 percent) of the group-sponsored ads aired so far are “dark money” ads (those from sponsors who do not have to disclose their donors) , which have aired at an estimated cost of over $68 million (Figure 2). In Senate races, 57.5 percent of interest group airings were sponsored by 501c3, 501c4 and 501c6 groups, sometimes referred to as social welfare organizations, which are not required to disclose their donors. Although dark money ad airings make up a smaller proportion of all interest group advertising this cycle compared to last, the total volume of dark money airings has increased in U.S. Senate races from 106,137 at this point in 2012 to 124,281 so far in 2014.