Citizens for Responsibility and Ethics in Washington wants the Federal Election Commission to investigate whether the American Action Network, a conservative advocacy group led by former Republican Minnesota U.S. Sen. Norman Coleman, violated campaign finance and tax laws during the 2010 election season.

Officials with the Citizens for Responsibility and Ethics said American Action declined to register as a political committee and file disclosure reports with the Federal Election Commission, in violation of federal law, despite spending millions of dollars during the 2010 election on advertisements targeting Democratic congressional candidates.

"It is past time for the FEC and the IRS to say enough is enough and finally crack down on this shadowy non-profit," said Melanie Sloan, the executive director of Citizens for Responsibility and Ethics. "What is the point of having laws on the books if they are not enforced? With the November elections only five months away, these agencies need to act now to make sure this election isn't a repeat of the 'anything goes' mentality of 2010."

American Action spent more than $25 million campaigning against Democrats during the 2010 election cycle, and has already paid for print advertisements and mailings for U.S. Rep. Chip Cravaack and other House Republicans during this election cycle.

As a tax-exempt organization, American Action is not required to publicly disclose its donors. Sloan's complaint to the FEC, and a previous one filed with the IRS, alleges that by spending two-thirds of its money on political activities, American Action violated its tax-exempt status. The complaint also alleges that the group has failed to properly disclose donors, contributions and expenditures.

American Action Network spokesman Dan Conston refuted Sloan's claims that the organization broke federal laws.

"American Action Network is a social welfare organization committed to advancing center-right policies. The Network complies with all laws and Internal Revenue Service and Federal Election Commission rules and regulations," Conston said. "CREW is a left-wing front group ... and we consider any action they take politically motivated and baseless."

Here's a look at Sloan's complaint:

6-7-12 AAN FEC Complaint