"During 2009 and 2010, labor unions reported spending a combined $46.7 million on messaging designed to aide their preferred federal political candidates, according to an analysis by the Center for Responsive Politics. Those candidates were overwhelmingly Democrats.
This figure represents 16 percent of all such spending by non-party committees -- the lowest amount in years, according to the Center's research.
By contrast, the four biggest-spending conservative groups together accounted for about $1 of every $3 spent on these types of political advertisements.
The U.S. Chamber of Commerce, American Action Network, American Crossroads and Crossroads Grassroots Policy Strategies reported spending a combined $97.6 million during the 2010 election cycle."
Union Muscle Eclipsed by High-Profile Conservative Groups During 2010 Election
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