President Obama recognizes that Citizens United threatens our democracy, while Mitt Romney fully supports it. In fact, Romney has said he would nominate Supreme Court Justices like the ones who brought us that infamous decision. So it's no surprise that the lion's share of spending made possible by that ruling is benefitting Romney.
That's the finding of the Center for Public Integrity, based on data made available by the Center for Responsive Politics. According to the Center for Public Integrity:
Since Labor Day, the once-unofficial start of the election season, 70 percent of outside spending on the presidential race made possible by the Citizens United Supreme Court decision has benefited Mitt Romney, according to a Center for Public Integrity analysis.
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Overall, since Labor Day, super PACs, nonprofits and other Citizens United spenders have spent $217 million on "independent expenditures," ads and campaign activities that urge voters to support or oppose a candidate and are reported to the FEC. The total does not include regulated political action committees and party spending.
Super PACs, which can receive and spend unlimited amounts from individuals, corporations and unions, are responsible for 55 percent of the spending. Nonprofits, which can act in the same way as super PACs but need not publicly disclose their donors, make up 44 percent of the total.
Here is CPI's pie chart showing just how lopsided the Citizens United spending is in the presidential race: