The federal complaint was signed by Patricia Morgan, chairman of the Rhode Island Republican Party, this afternoon and notarized. Party officials will mail the document to FEC offices in Washington later today, according to spokesman Chuck Newton.

“We believe very strongly that filing this complaint is the right thing to do,” Morgan said in a statement. “This has not been a quiet episode. These contributions have received wide coverage already. But this does not detract from that fact that the practice reported is clearly illegal.”

Brown and his campaign engineered an arrangement whereby Maine, Massachusetts and Hawaii were induced to give his campaign a total of $25,000, while a handful of wealthy Brown backers agreed to give the state parties a total of $30,000.

Because Brown's individual donors had each given him the legal maximum, the episode raised the question of whether Brown -- a self-styled reform candidate for GOP Lincoln D. Chafee's Senate seat -- had created a mechanism for evading the lawful limits on contributions.

Brown has said that the maneuver, though legal, created "an appearance problem," and decided to return the money to the three states.

The five-page complaint signed today by Rhode Island Republicans relies largely on information in media reports to make its case against Brown.

“Federal law prohibits campaign committees from earmarking contributions from maxed out donors through state party committees in an effort to evade the contribution limits. According to recent media reports, Brown campaign and Democratic state party officials have indicated that such a scheme may have been set in motion,” reads the complaint released publicly today for the first time.

“Accordingly, the Republican state parties hereby request that the commission undertake an immediate investigation into this matter and, if the alleged scheme violates the … regulations, impose the maximum penalties under law.”

A spokesman for the FEC said this afternoon that should the commission decide to investigate, the maximum civil penalties would depend on whether the violations were “knowing and willful.”

In the case of a violation that’s not willful, the maximum penalty is the greater of $5,000 or the amount involved, according to FEC spokesman George Smaragdis.

Fines increase dramatically to a minimum of 300 percent of the amount involved for willful violations.