"Words can't express how sorry I am for the harm I have caused to others, especially my family," Plotkin said.

Plotkin was charged in 2006 in a scheme that involved David Pajcin, another Goldman Sachs analyst, and Stanislav Shpigelman, who met Plotkin in college and worked as an analyst at Merrill Lynch & Co. Inc.'s mergers and acquisitions division.

Assistant U.S. Attorney Helen Cantwell said the trio conspired on some of the most innovative and complicated insider-trading schemes since those of the 1980s.

In one instance, a New Jersey grand juror leaked information so Plotkin and Pajcin could learn details of an investigation of accounting fraud accusations against Bristol-Myers and several of its executives.

In a second plot, Pajcin and Plotkin arranged for a man to become a forklift operator at a printing plant so he could steal early copies of a market-moving column in BusinessWeek magazine.

Prosecutors say Shpigelman provided Plotkin and Pajcin with information on deals to give them an advantage in their trading.

In exchange for information on six different pending mergers or acquisitions, Shpigelman received cash and promises of future payments based on a percentage of profits, authorities said.

Although the charges carry a potential maximum prison term of 165 years, Plotkin signed a plea agreement in which he promised not to appeal any sentence between four years and nine months and five years and 11 months in prison.

Seeking to salvage his reputation and quell a media storm stirred by his guilty plea to disorderly conduct charges, the Republican senator Tuesday denied making a sexual advance to an undercover officer in a Minneapolis airport men's room two months ago.

"I am not gay and never have been," Craig declared at a Boise news conference with his wife, Suzanne, at his side.

But even as he denied making an advance, the case sent shock waves through Republican circles. Senate Republican leaders called for an ethics investigation and vowed to consider other sanctions.

Former Massachusetts Gov. Mitt Romney, whose Idaho presidential campaign was headed by Craig until the charges came to light, compared the senator's behavior to former President Clinton's encounter with a White House intern and to former Rep. Mark Foley, R-Fla., who resigned last year in a scandal involving male House pages.

The charge grew out of a June 11 incident at Minneapolis-St. Paul International Airport in which an officer investigating lewd-conduct complaints about activity in the restroom arrested Craig for allegedly making a sexual advance. The arrest and the senator's Aug. 1 guilty plea became public Monday, when they were reported by the Capitol Hill newspaper Roll Call.

Craig, 62, was ordered to pay $575 in fines and fees and given one year's probation. A sentence of 10 days in the county workhouse was stayed.

At the news conference, Craig, a leading voice on issues affecting the West and a consistent opponent of gay-rights legislation, apologized for his handling of the incident, saying he regretted his guilty plea.

He said he had retained a lawyer to review the plea, although he signed court papers declaring he had read the police report and understood the nature of the crime and paid the fine — which defense experts said would make a challenge difficult.

Craig said he pleaded guilty because his hometown newspaper, The Idaho Statesman, had been conducting an eight-month investigation into his sexual orientation. He said he hoped that resolving the case quietly — without telling his family, friends, staff or colleagues — would settle the matter without bringing it to light for what he called the newspaper's "witch hunt."

"I overreacted in Minneapolis, because of the stress of The Idaho Statesman investigation and the rumors it has fueled around Idaho," said Craig, who took no questions.

Craig has confronted sexually related accusations before. In 1982, he denied involvement in a congressional-page sex scandal.

The Statesman on Tuesday reported on rumors that Craig had engaged in restroom sexual encounters with other men. The newspaper began its inquiry after a gay activist blogger, Mike Rogers, published a claim that Craig had sex with men. Rogers cited anonymous sources.

The Statesman quoted an anonymous man who claimed he had sex with Craig in a restroom at Union Station in Washington, D.C. The newspaper, which interviewed 300 people, described other allegations but did not name those who made them.

In a May interview that the newspaper published Tuesday, Craig denied having had gay sexual encounters and specifically denied restroom encounters.

"I'm going to have to leave it up to other people to weigh the care we took. I'm a bit disappointed" with Craig's complaints, said Vicki Gowler, the newspaper's top editor. "We were quite responsible, and we took great care with the story."

Craig already was under pressure from Republicans to give up the seat he has held since 1991 rather than risk handing Democrats what has been a safe seat. He said he'll announce next month whether he will seek re-election.

Pressure accelerated Tuesday. The mug shot from Craig's arrest was broadcast on CNN accompanied by a headline: "Senator's Bathroom Bust." The Drudge Report went with the headline "Brokeback Bathroom." And the detailed arrest report was available on the Internet.

Greg Smith, an Idaho pollster who has worked for Craig, said it was "almost certain" the senator would not seek re-election.

David Adler, a political-science professor at Idaho State University, noted that GOP leaders would be unlikely to support any interest Craig might have in trying to hold his seat "since they would fear losing a seat that has been safe for so long."

Adler said Craig's swift resignation as co-chair of Romney's presidential campaign in Idaho provides a "good measure of the fever that has been inflicted."

Patrick Sammon, president of the Log Cabin Republicans, the largest organization for gays in the GOP, said Craig's ability to continue serving is "in serious doubt."

If Craig resigns, Republican Gov. C.L. "Butch" Otter will appoint a successor, most likely a Republican, to serve the remainder of the term.

A former Democratic congressman, Larry LaRocco, is campaigning to replace Craig. LaRocco was elected to the House in 1990 but lost the seat in the 1994 GOP takeover.

LaRocco said he believes a Democrat can win even though none has been elected to the Senate from Idaho since Frank Church, who lost the seat in 1980. "People are in a plate-throwing mood out here, regardless of what happened with Larry Craig," LaRocco said.

Craig now is fighting a multifront battle, first and foremost a longshot bid to undo his guilty plea and the likely ethics probe, while also trying to shore up support among constituents should he decide to seek a fourth six-year term.

In his guilty plea, according to court records, Craig acknowledged engaging in physical "conduct which I knew or should have known tended to arouse alarm or resentment of others." Criminal-defense lawyers said it would be difficult for the senator to have the case reopened.

Successful motions to withdraw guilty pleas usually meet a high threshold, such as showing the person was misled into entering the plea, his constitutional rights were violated or there was wrongdoing by prosecutors, Minneapolis criminal-defense lawyer Peter Wold said.

But Craig's written plea specified the charges related to the airport incident, that he knew the judge couldn't accept a guilty plea from a person who felt he was innocent and that he was making no claim of innocence.

If he's successful in overturning his plea, Craig likely will have to face a public trial, Wold said.

McGraw-Hill is a New York-based financial and education information services company. McGraw-Hill had no immediate comment because it said it wasn't aware of the suit.

The ferry is in only its second day of commercial voyages between Honolulu, Maui and Kauai. The Superferry was originally scheduled to start sailings on Tuesday, but the company moved the start date to Sunday and issued $5 one-way tickets to launch the service in advance of a legal challenge by environmentalists.

More than 90 percent of the available space was filled as passengers rushed to experience Hawaii's first modern interisland ferry service at bargain basement prices.

A Superferry spokeswoman said today's Maui and Kauai trips were sold out. The 350-foot vessel can carry more than 850 people and 250 vehicles, but the company projects an average load of 400 passengers and 110 vehicles.

The first day of Hawaii Superferry service to the island of Kauai on Sunday was disrupted by hundreds of protesters on surfboards, swimming in the path of the vessel and lining the docks at Nawiliwilil Harbor, in advance of the courtroom battle over environmental issues today. The U.S. Coast Guard intervened after two hours to clear a path for the Superferry to enter the harbor.

On Thursday, the Hawaii Supreme Court decided that the state was wrong to have exempted ferry-related improvements at Maui's Kahului Harbor from the state's environmental review law.

The Supreme Court ruled on an appeal of an earlier decision by Cardoza dismissing a complaint filed against the Hawaii Department of Transportation by three citizens' groups - the Maui Tomorrow Foundation, the Sierra Club and the Kahului Harbor Coalition. Cardoza had ruled the groups did not have standing to bring the complaint.

The Supreme court ruled that they do have standing and in addition ordered an environmental assessment of the harbor improvements.

Isaac Hall, the attorney for the groups, hopes to expand the case to involve the Kauai sailings as well.

In September 2005, Judge Helen Gillmor dismissed the suit brought by the three groups seeking to require the Superferry to prepare a full Environmental Impact Study, EIS.

The groups filed suit after several months of meetings with Superferry head John Garibaldi produced no agreement for an EIS. Other groups, Kauai County and Maui's Mayor and County Council have called for an EIS review as well, but are not parties to the lawsuit.

What the Supreme Court ordered Thursday is not an EIS, but a less extensive environmental assessment. Even that could take six months to a year to complete.

Concerns range from increased traffic on Maui and Kauai, collisions with whales, impact on campsites and the creation of a new, rapid dispersal method for alien species, the Sierra Club says.

Because the court case involves concerns about impacts only at Kahului Harbor, Judge Cardonza's temporary restraining order does not prevent the Superferry from sailing between Honolulu and Kauai.

A second charge of interference with privacy against the 62-year-old senator was dismissed. Mr. Craig was fined more than $500 at the Aug. 8 proceedings and was placed on unsupervised probation for one year. His 10-day jail sentence was suspended, according to a copy of a court document in the case.

According to a police report obtained by Roll Call, the Capitol Hill newspaper that disclosed the episode and guilty plea today, a plainclothes police officer investigating complaints of sexual activity in the bathroom arrested the senator on June 11 after what the officer described as sexual advances made by Mr. Craig from an adjoining stall.

Roll Call reported that the officer said Mr. Craig tapped his foot as a signal to engage in lewd conduct, brushed his foot against the investigator's and waved his hand under the stall divider several times before the officer showed him his badge. After his arrest, the senator denied any sexual intent and in a statement issued this afternoon he attributed the matter to a misunderstanding.

"At the time of this incident, I complained to the police that they were misconstruing my actions," Mr. Craig said in a statement. "I was not involved in any inappropriate conduct.

"I should have had the advice of counsel in resolving this matter. In hindsight, I should not have pled guilty. I was trying to handle this matter myself quickly and expeditiously."

Mr. Craig, whose seat is up for election next year, is the second Republican senator in recent weeks to find his personal behavior under scrutiny. Senator David Vitter of Louisiana was implicated in a separate case in the Washington area when his phone number turned up in the records of an escort service. He made a public apology for what he described as "a very serious sin in my past," but he has not been charged with any crime.

In the Senate, Mr. Craig, who is married and has three children, is known for his advocacy for the rights of gun owners and has a close association with the National Rifle Association. When Republicans controlled the Senate in the last Congress, Mr. Craig was chairman of the Veterans Affairs Committee. He is a former member of the party's Senate leadership. He represented Idaho in the House before first winning election to an open Senate seat in 1990 and he was easily re-elected in 1996 and 2002.

In 2006, Mr. Craig publicly rejected allegations by a gay rights advocate that he had engaged in a homosexual behavior, calling them "completely ridiculous."