While third-party spending in support of Democrats running for office has largely kept pace with spending on behalf of Republican candidates, Republicans have benefited far more from so-called "dark money," an analysis by the Sunlight Foundation finds.
The foundation's analysis of political contributions from "dark money" organizations — politically active 501(c)(4) social welfare organizations or 501(c)(6) trade associations that, unlike super PACs, do not have to disclose their donors — found that Republican-leaning groups had spent $94.6 million in the current election cycle, while Democratic-leaning groups had spent $28.4 million. Some $1.9 million in expenditures could not be classified. The analysis also found that for both parties, much of the anonymous spending was focused on a handful of tight Senate races in Alaska, Arkansas, Colorado, Iowa, and North Carolina.
According to Sunlight, the biggest spender in the current election cycle is the U.S. Chamber of Commerce, which directed nearly all of its $31 million in reported spending into supporting Republican candidates or opposing Democrats running for office. The chamber was followed by Crossroads GPS, part of the network of organizations founded by Karl Rove and Ed Gillespie in the wake of the Supreme Court's Citizens United decision, which spent $23.7 million to defeat Democratic candidates. Coming in a distant third was the League of Conservation Voters, which has spent $9.5 million to support Democrats running for office.
While Internal Revenue Service rules limit the political activities of social welfare organizations, such groups may spend millions of dollars in "independent expenditures" to support or oppose individual candidates so long as they file a disclosure form with the Federal Election Commission that includes the amount and type of expenditure — for example, television ads — and the candidate who is the target of the spending. The analysis further notes that reported spending by "dark money" groups tends to increase just before an election, as non-filers who had been funding issue ads switch to directly advocating for or against candidates.