American Crossroads and Crossroads GPS, the sister conservative organizations that hope to raise $52 million in order to defeat Democratic candidates in 2010, is already close to spending a combined $20 million in ads. After spending an initial $14 million in ads to boost the GOP’s chances at taking control of the Senate, Crossroads is ready to spend an additional $4.2 million for ads in Senate races in Colorado, Nevada, Washington, Missouri, Pennsylvania, Illinois, and Florida. Now, Mike Allen of Politico reports that the two groups will begin running ads in competitive House races shortly.

Crossroads GPS, the leading outside group airing ads in Senate races, does not have to disclose its donors since it is a 501(c)4 “social welfare” organization. But as a 501(c)4, it is supposed to focus on “issue advocacy” rather than deliberately urge voters to support or oppose specific candidates for office. Now, the heads of Democracy 21 and the Campaign Legal Center have asked the IRS to look into the group’s status, maintaining that Crossroads GPS “was organized to participate and intervene in the 2010 congressional races while providing donors to the organization with a safe haven for hiding their role.” J. Gerald Hebert of the Campaign Legal Center explains:

While the abuses of 501(c)(4) tax designation for no-fingerprint political attack ads seems rampant in this election cycle, the most blatant certainly appears to be Crossroads GPS. The group makes almost no effort at all to hide the fact that it was created principally to impact the 2010 elections, and to take money from those interested in contributing to their efforts but doing so anonymously. The IRS has a duty to ensure that groups are not violating their tax status in this election cycle, and Crossroads GPS certainly seems like a logical place to start.