Washington (CNN) -- Are American Crossroads and Crossroads GPS comparable to labor unions and MoveOn.org? Democratic activists scoff at the question. But Steven Law, Crossroads' CEO, says yes. "American Crossroads was conceived as an answer to the hundreds of millions of dollars that unions and MoveOn.org and other groups on the left have been spending for years to support Democrats," Law said. "So we started American Crossroads because we thought there ought to be a way for us to try and level the playing field." Adam Ruben, political director for Moveon.org, says it's a fundamentally different approach to political engagement.
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How does labor union political activity square up with super PAC?
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Union representatives oppose comparison on principle
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Election could be a test run for new era of big money in politics
American Crossroads
Crossroads
American Crossroads
American Crossroads
Representatives from @placeholder say they are experimenting with new ways to get out the vote online and through technology but acknowledge that it doesn't approach the boots-on-the-ground power the unions have.
American Crossroads
Crossroads
American Crossroads
American Crossroads
"Conservative groups like @placeholder outspent liberal ones by a 2-1 margin in the 2010 cycle and are poised to spend even more in 2012.
Democratic
Democrats
Law is unfazed by the criticism, saying, "Nobody thought that was controversial when they're helping @placeholder.