The Federal Election Commission filed a lawsuit Monday against the Club for Growth, alleging that the pro-business, anti-tax Republican group violated federal election law in recent years by raising and spending millions on federal campaign activities without registering as a political committee.

The lawsuit is the first to be generated from the numerous complaints the FEC received that target the “soft money groups” that spent millions of unregulated funds during the 2004 elections. The use of soft money was banned following the 2002 elections.

“The Club itself has repeatedly asserted that its purpose is to ‘elect pro-growth congressmen’ and ‘defeat status quo incumbents,’” according to the suit the FEC filed in U.S. District Court for the District of Columbia. “In violation of the Federal Election Campaign Act, however, the Club has never registered as a political committee with the Commission and has failed to report to the Commission its receipts and disbursements, which include more than a quarter million dollars in prohibited contributions from corporations and more than $9 million in contributions that exceed the limits of the Act.”

The Club raised and spent an estimated $22 million over the course of the 2004 cycle.

In a lengthy statement released Monday, Club for Growth President Pat Toomey called the lawsuit “outrageous” and vowed to “vigorously defend the rights of our members, and all Americans, to organize and speak out about our government’s policies.”

“The FEC’s claims and legal theories are a bizarre interpretation of the Club’s mission, the Constitution, the laws adopted by Congress and their own regulations governing nonprofit organizations,” Toomey said.

Toomey also alleged that the Democratic complaint from which the lawsuit stems “had no supporting detail” and that the FEC had only recently “resurrected it as a platform to seek to take away our members’ rights and exact a huge civil penalty from the Club.”

Since its founding in 1999, the organization has played an increasingly influential role in Congressional elections. But its willingness to violate the late President Ronald Reagan’s “11th Commandment” has also caused heartburn for GOP leaders, as the Club has continued to seek out and support conservative primary challengers against incumbents. In 2004, the group supported Toomey, then a Congressman, in his bid to oust Sen. Arlen Specter (R-Pa.).