BOISE, Idaho (AP) — Former Republican U.S. Sen. Larry Craig of Idaho was sued Monday by federal election regulators who contend he misused some $217,000 in campaign funds for his legal defense after his arrest in a 2007 airport bathroom sex sting.

Federal Election Commission officials said in their complaint filed in U.S. District Court in Washington, D.C., that Craig should repay the money and pay a fine.

The FEC contends the three-term U.S. senator's campaign account, Craig for U.S. Senate, paid at least $139,952 to the law firm Sutherland, Asbill and Brennan in Washington, D.C., and $77,032 to Kelly & Jacobson in Minnesota for legal services related to his guilty plea to disorderly conduct.

Craig had been accused of soliciting sex in a bathroom at the Minneapolis-St. Paul International Airport. An undercover officer said Craig tapped his feet and signaled under a stall divider that he wanted sex.

Regulators said the campaign money was converted to personal use because Craig's defense in Minnesota had no connection to his campaign for federal office.

"Mr. Craig used these funds converted from his campaign committee to pay legal expenses he incurred in connection with his arrest, guilty plea, and subsequent efforts to withdraw his guilty plea in Minnesota," according to the complaint. "These legal costs were not made in connection with his campaign for federal office or for ordinary and necessary expenses incurred in connection with his duties as a senator."

Regulators added "the expenses ... would have existed irrespective of his duties as senator."

The FEC said it was unable to resolve the matter through "informal methods of conference, conciliation and persuasion" with Craig earlier this year.

The commission, which voted 5-0 last month to pursue the lawsuit, is also seeking penalties of up to $6,500 from the former senator and his treasurer, Kaye O'Riordan.

A call to Craig's lobbying firm, New West Strategies in Washington, D.C., wasn't returned Monday evening.

O'Riordan also didn't return a phone call to her Boise home.

After Craig's guilty plea, he received a sentence of 10 days of jail time and a $1,000 fine; the jail time and half of the fine were suspended.

After the arrest became public, Craig publicly maintained his innocence and his heterosexuality, insisting he only pleaded guilty to keep the embarrassing situation quiet. He initially told a crowd in Boise that he intended to resign, then opted to serve out his term until January 2009.

In 2008, the Minnesota Court of Appeals rejected Craig's attempt to withdraw his guilty plea.

In January 2009, the three-term senator from Payette, Idaho, decided against asking the Minnesota Supreme Court to void the conviction, marking an end to that phase of his legal wrangling.

According to the FEC complaint, lawyers for Craig wrote in a September 2007 letter to the Senate Ethics Committee that his arrest and conviction were "purely personal conduct unrelated to the performance of official Senate duties."

On Feb. 13, 2008, the Senate Ethics Committee issued a "Public Letter of Admonition" unanimously concluding that, among other matters, Craig hadn't complied with Senate rules requiring members to seek approval of any payments for "legal expenses" paid with funds of a principal campaign committee.

In its 11-page filing, the FEC also asked a judge to order Craig to pay the agency's expenses in the latest case.

In addition to the money targeted by the FEC complaint, Craig spent thousands more from his campaign fund related to the arrest.

However, the FEC concluded that using the money to pay for representation during a Senate Ethics Committee inquiry and to pay for a public-relations firm to respond to media inquiries regarding his arrest and misdemeanor conviction were permissible uses of campaign funds.