A New Orleans political consultant who is Senator Kennedy’s brother-in-law, Raymond Reggie, has been operating in Democratic circles for the last three years as an undercover informant for the FBI, sources close to the matter said yesterday.

At a federal court hearing yesterday morning, Reggie, 43, who organized fund-raisers for President and Mrs. Clinton, pleaded guilty to two felony charges, bank fraud and conspiracy. Prosecutors described check-kiting and loan fraud schemes he operated involving three Louisiana banks, but they did not publicly detail his cooperation with the government.

The New York Sun reported yesterday that an unnamed witness with ties to a prominent political figure has been involved in recent federal investigations of campaign fund-raising violations, including a probe into alleged financial misreporting in Mrs. Clinton’s bid for the Senate in 2000. The informant, described in court papers only as a “confidential witness,” was part of an FBI plan to secretly audiotape conversations with political operatives, including a well-known person who prosecutors said was seeking to funnel donations from foreigners to federal campaigns.

Several people with knowledge of the case identified Reggie as the informant described in the Sun article.

In a brief interview, the first assistant U.S. Attorney in New Orleans, Jan Mann, said of the Sun story, “I wasn’t sure if anybody made any of these connections yet or not.” She declined to describe the investigations in which Reggie helped the government. “We’re not handling anything outside of the case on Ray Reggie, so it certainly wouldn’t be in my realm to talk about anything else,” she said.

Reggie’s lawyer, Michael Ellis, declined to comment for this article.

The disclosure that Reggie was surreptitiously recording conversations for the FBI may have caused some heartburn yesterday for Democrats who have had contact with him since 2002.

Reggie was a regular presence at Mr. Clinton’s side when he visited New Orleans during his presidency and thereafter. Just last September, Mr. Clinton had lunch in that city with Reggie, as the former president swung through town to sign his autobiography and attend a $10,000-a-head Democratic Party fund-raiser, the Times-Picayune newspaper reported. A former congresswoman and ambassador to the Vatican, Lindy Boggs, joined Reggie and Mr. Clinton at the lunch, as did two federal judges whom Mr. Clinton appointed.

When Mrs. Clinton traveled to New Orleans in May 2000 to raise $100,000 for her Senate campaign, Reggie was on the host committee.

An attorney for the Clintons, David Kendall, had no immediate response yesterday to questions about Reggie’s role in Mrs. Clinton’s Senate campaign or about the possibility that Reggie might have taped one or both of the Clintons.

Reggie is expected to be a witness in a federal criminal case involving a finance official on Mrs. Clinton’s campaign staff, David Rosen. In a trial scheduled to start at Los Angeles on May 3, Mr. Rosen, 40, faces charges that he caused false donation and expenditure reports to be filed with the Federal Election Commission in connection with a fund-raising gala at Hollywood in August 2000.

Court documents indicate that in September 2002, a confidential witness, identified by other sources as Reggie, taped an unwitting Mr. Rosen in a conversation discussing his role in the 2000 gala. In an affidavit submitted to a federal magistrate, an FBI agent asserted that the informant “was involved in the planning of the Clinton Gala.”

In June 2000, Reggie and his wife, Mary Michelle, were guests at a state dinner. They also stayed overnight at the White House as guests of the Clintons.

Mr. Rosen’s defense attorney, Paul Sandler of Baltimore, refused to comment yesterday on the disclosure of Reggie’s role as an informant or on what impact his secret recording might have on Mr. Rosen’s case. “I have nothing to say. I’m getting ready for trial in 10 days,” Mr. Sandler said.

A former Internet executive who helped organize the August 12, 2000, Hollywood fund-raiser, Peter Paul, said in an interview last night that he was certain Reggie was not a key player in the gala. “If he had a role, it was a very, very small role,” Paul said.

However, campaign finance records provide some indication that Reggie might have at least attended the fundraiser for Mrs. Clinton at a radio’s executive’s mansion in the Brentwood hills of Los Angeles.

On August 28, 2000, the committee that officially sponsored the event, New York Senate 2000, recorded a donation from Reggie of $1,330.

Reggie took out a full-page ad in a “tribute book” distributed to guests at the gala. “You have demonstrated as the president and first lady of the United States that you were willing to ‘pay any price, bear any burden, meet any hardship, support any friend, oppose any foe, in order to assure the survival and the success of liberty,'” the ad read. It was signed, “With gratitude, Ray Reggie.”

On separate occasions, Reggie gave another $6,000 to committees connected with Mrs. Clinton’s campaign. Overall, Reggie gave about $29,000 to Democratic candidates over the past six years, Federal Election Commission filings show. Reggie also served on the national finance committee for Vice President Gore’s presidential bid in 2000, according to a New Orleans publication, cityBusiness.

Reggie’s sister, Victoria, is married to Senator Kennedy of Massachusetts. A spokeswoman for Mr. Kennedy did not return several phone calls yesterday seeking comment for this story. Reggie is also the son of a prominent Louisiana judge, Edmund Reggie, who was a close friend of President Kennedy.

The younger Reggie is close to and has done consulting work for the former mayor of New Orleans, Marc Morial. Press reports in Louisiana have suggested that prosecutors’ interest in Reggie may have stemmed from a desire to get information from inside Mr. Morial’s inner circle. Mr. Morial has not been charged with any crime.

The bank-fraud charges against the Reggie date to 2001 and earlier. Court records indicate his plea deal with the government was reached in 2002. However, the charges were not filed publicly until February of this year.

Reggie, who ran an advertising buying and consulting firm known as Media Direct, has admitted to using a forged contract with the Census Department to obtain a $6 million line of credit from a Louisiana bank. At the hearing yesterday, he acknowledged using that line of credit to cover a check-kiting scheme at two other banks. One bank lost $3.5 million, court papers said. His sentencing was set for October 23. The maximum penalty on the two charges is 35 years in prison and a fine of up to $1.25 million.

Reggie also faces a separate, unrelated state trial in Louisiana next month for allegedly impersonating a police officer. The felony charge stems from a 2002 incident in which Reggie allegedly used a blue light to stop another vehicle.

“He pulls over a car full of young girls, tells them he’s a cop; and wants one of them to get out; tried to get them to follow him somewhere,” the prosecutor handling the case, Kim McElwee, said in an interview.

Ms. McElwee complained that she has had great difficulty obtaining routine evidence for the case. “I’ve never had a case quite like this,” she said. “People say they have a document. I call back. Not only is the document gone, they’re gone. It’s bizarre.”

Reggie, who has maintained his innocence, has waived his right to a jury trial. Ms. McElwee said the judge will probably acquit Reggie. “I’m getting entertainment out of this. I’m certainly not going to get a conviction,” she said.

LOS ANGELES — After less than five hours of deliberations, a federal jury acquitted the national finance director of Senator Clinton’s 2000 campaign Friday on charges that he deliberately understated the amount of money spent on a star-studded concert held to raise money for Mrs. Clinton’s Senate race.

David Rosen, 38, a Chicago-based fund-raising consultant, was found not guilty on two felony counts that alleged he caused the filing of false campaign finance reports with the Federal Election Commission. If convicted, he faced the possibility of up to 10 years in prison and a fine of up to $500,000.

Upon hearing the verdict Friday morning, Mr. Rosen forcefully embraced his lead defense lawyer, Paul Mark Sandler, slapping him on the back. Several of Mr. Rosen’s family members sitting in the front row of the gallery cried out with joy. Mr. Rosen’s wife, Melissa, and her father sobbed. Even Mr. Sandler, a veteran trial lawyer from Baltimore, briefly fought back tears.

“Holy cow,” Mr. Rosen said as he turned to his family.

Moments later, he told reporters he is eager to get back to his fund-raising business, which was all but shuttered while the legal saga unfolded. “It’s been five years this has been going on,” he said. “I have closure in my life.”

The defendant’s mother, Roberta Rosen, said the prosecution was driven by politics. “I think it was totally, 100% political from the onset,” she said. She described her son as a “little minnow” caught up in a saga involving much bigger fish.

Prosecutors, who wore long faces after the verdict, said little. “We wouldn’t have brought the case if we didn’t think there was reason to bring it,” the lead prosecutor, Peter Zeidenberg, told reporters.

The Justice Department has denied that political considerations played any role in the prosecution. “We respect the jury’s verdict,” a department spokesman, Bryan Sierra, said. “We continue to believe that honest, truthful, and legal reporting to the Federal Election Commission is a fundamental and important principle of the election system. We will continue our effort to prosecute those who violate the law.”

In a statement, an attorney for Senator Clinton, David Kendall, hailed the verdict. “”We have said from the beginning that, when all the evidence is in, David would be vindicated. That has come to pass, and Senator Clinton is very happy for David and his family,” the senator’s lawyer said.

Jurors who spoke with reporters after yesterday’s proceedings said the evidence and witnesses left too many questions unanswered about the August 12, 2000, gala, which featured Cher, Dylan McDermott, and others. The jurors cited, in particular, the government’s failure to call as witnesses the main financial backer of the concert, Peter Paul, and the lead organizer of the event, Aaron Tonken.

“Reasonable doubt was the huge key here,” the jury foreman, Michael Johnson, said. Mr. Johnson, a radiological equipment technician, said the prosecution’s case left him with “lots of question marks.”

Mr. Johnson, 40, said the jury of seven men and five women was split fairly evenly when it took its first vote after deliberations began Thursday. The jurors gradually swung toward a not guilty verdict, he said.

Prosecutors never told the jury why Paul and Tonken weren’t called, but legal analysts said it was likely due to the serious credibility problems of both men. Paul has four felony convictions and is awaiting sentencing on a stock fraud charge. Tonken is serving a five-year prison sentence for mail and wire fraud related to charity fund-raisers he ran.

Several jurors also said they were troubled that one of Mrs. Clinton’s closest aides on the 2000 campaign, Kelly Craighead, did not testify. One prosecution witness said that in a hotel lounge the night before the gala Mr. Rosen and Ms. Craighead had a heated argument about the cost and scope of the event. Mr. Rosen denied that.

Mr. Zeidenberg mentioned Ms. Craighead in his closing to the jury, implying that the defense should have called her if she would have backed up Mr. Rosen’s version of events. However, the jurors appeared to hold her absence against the prosecution.

The jurors also were not impressed by many of the witnesses who did appear for the prosecution. Two of those who implicated Mr. Rosen in knowing about the cost overruns, Raymond Reggie and James Levin, were admitted criminals.

One juror, Angelo Sanders, said he disregarded Reggie’s testimony after it emerged that Reggie carried a blue police light in his car and had been accused of impersonating an officer. Reggie said he had an honorary police commission and used the light to escort dignitaries. The impersonation case was recently dropped, though Reggie did plead guilty to two unrelated bank fraud charges.

“The blue light on the car, that kind of closed the deal,” said Mr. Sanders, 29, who works for a hip-hop record label.

Mr. Johnson said he wasn’t sure what to make of Mr. Levin, a Chicago businessman who recently admitted to contracting fraud and offering kickbacks, but who also told the court he is a “dear friend” of President Clinton. The jury foreman said he thought Mr. Levin was embellishing, until defense lawyers played an ABC News “20/20” story about Paul that showed pictures of Mr. Levin side-by-side with Mr. Clinton in various settings.

During the trial, prosecutors struggled to explain to jurors why Mr. Rosen would have thought that Mrs. Clinton’s campaign would benefit financially by under-reporting the expenses, most of which were paid by Paul through various companies he controlled.

In his defense, Mr. Rosen maintained he didn’t know that Paul and Tonken spent $700,000 more than the roughly $525,000 in concert expenses reported to the FEC.

Toward the end of the case, prosecutors honed in on two specific items Mr. Rosen didn’t report: his $9,300, three-week stay at the Beverly Hills Hotel, paid for by Tonken, and the use of Tonken’s Porsche 911 convertible during that period. Mr. Rosen said he didn’t report those items because he considered them personal gifts unrelated to the gala.

Jurors largely ignored that issue. “They spent too much time on that,” Mr. Sanders said, pointing out that the indictment said Mr. Rosen knew that spending for the gala was “substantially more” than what was reported. “A $5,000 or $10,000 hotel bill isn’t substantial when you’re talking about $1.2 million,” the juror said.

Another juror, Stacy Spencer, griped about the tedium of some evidence, particularly relating to a now-defunct legal distinction between “hard” and “soft” money in political campaigns.

“I really don’t ever want to hear those terms again,” Ms. Spencer said

Mr. Sandler told reporters that Mr. Rosen deserves accolades for taking the stand in his own defense. “Like I told the jury, I think he’s an American hero,” Mr. Sandler said. “He was being surrounded for so many years by such responsible people telling him that he had done wrong and he stood up and he had the courage to come to court and to testify and to face the jury and tell them the truth.”

While the worst is now over for Mr. Rosen, the legal aftershocks from the August 2000 concert are likely to continue. The Federal Election Commission is considering whether to fine the fund-raising committee that ran the gala, New York Senate 2000, for the allegedly false reports. In addition, a lawsuit Paul brought against President and Mrs. Clinton, Mr. Rosen, Mr. Tonken, Mr. Levin, and others remains pending in a California court.

A conservative group that helped Paul file the lawsuit said yesterday that the case against Mr. Rosen was damaged when prosecutors declared at the outset that the Clintons were not involved.

“It’s a political hot potato that (prosecutors) didn’t want to handle,” a spokesman for Judicial Watch, Brandon Millett, said. “Government lawyers presented a watered-down, impotent case. They ignored key evidence to keep Bill and Hillary Clinton out of the trial.”

In a tape secretly recorded by Reggie in 2002 but never introduced at trial, Mr. Rosen reportedly complained that he was being used by the Clintons as a “guinea pig” in the civil lawsuit.

Yesterday, the former fund-raising chief said he harbors no ill will towards Mrs. Clinton. “I’ve always thought very highly of the senator,” he said.

One of Mr. Rosen’s first public comments yesterday was an offer of thanks to “the people who helped me pay for the finest legal team.” He declined to name the benefactors.

Mr. Sandler said Mr. Rosen borrowed money from friends to pay his legal bills. During the trial, which lasted over two weeks, Mr. Rosen was also represented by a former Democratic National Committee lawyer who is the lead attorney’s cousin, Joseph Sandler of Washington, D.C., and by a Los Angeles attorney, Michael Doyen.

Mr. Zeidenberg, and the other prosecutor on the case, Daniel Schwager, are based in Washington, D.C. at the Justice Department’s public integrity section.