Within hours of President Bush’s announcement that he was nominating Harriet Miers to the Supreme Court, the phone at Lawrence Littwin’s Upper East Side apartment began ringing off the hook. The callers were reporters eager to hear about the five stormy months Mr. Littwin spent working for the nominee nearly a decade ago.

“I’ve had more than one call,” Mr. Littwin said with a laugh last week.

At first glance, Mr. Littwin, 70, seems an unlikely figure to pose any sort of hindrance to a Supreme Court nominee. A pioneer in adapting early computer technology to state-run lotteries, he helped New York deploy its first online Lotto system in 1980 and spent more than 20 years setting up lottery networks for Control Data Corporation.

Mr. Littwin retired from the company in 1992. In 1997, he got word that the Texas Lottery Commission was searching for a new executive director. Egged on by his wife, Mr. Littwin applied. In June of that year, he flew to Texas and, after a three-hour interview, got the job.

As fate would have it, the hiring was announced by Ms. Miers, whom George W. Bush, then the governor of Texas, had installed as head of the lottery board two years earlier. Speaking to the press, she gushed about Mr. Littwin: “He has all the background, all the experience, all the technology knowledge.”

Less than five months later, Mr. Littwin was fired. Why Ms. Miers and others suddenly lost confidence in the lottery veteran has been the subject of years of legal maneuvering and political intrigue.

In a federal lawsuit, Mr. Littwin alleged that the firing was the result of his uncovering widespread graft involving Texas officials and the company that held a lucrative contract to run the lottery, GTECH of West Greenwich, R.I. Mr. Littwin also said he was dismissed because he had embarked on a thorough investigation of the company’s dealings in Texas that threatened to draw attention to one of the most politically sensitive aspects of Mr. Bush’s life story: whether political connections helped him gain a National Guard slot during the Vietnam War.

GTECH’s top lobbyist in Texas was a former Democratic lieutenant governor with long ties to the Bush family, Ben Barnes. Mr. Barnes received a $3 million-a-year retainer from the company and $23 million when he ended his relationship with the firm in 1997. Mr. Littwin contended that Mr. Bush’s allies, including Ms. Miers, ignored and overlooked GTECH’s misconduct and poor performance because Mr. Barnes held a potentially damaging secret: that he pulled strings to get Mr. Bush into the National Guard. The lottery veteran’s assertions relied in part on an anonymous letter sent to federal prosecutors alleging in some detail that GTECH’s hold on the Texas lottery contract was the result of just such a quid pro quo.

Mr. Littwin’s contention seemed farfetched until Mr. Barnes was forced to give a deposition in the lawsuit in September 1999. Mr. Barnes acknowledged that he helped Mr. Bush obtain the National Guard slot at the request a close friend of the Bush family, Sidney Adger. However, Mr. Barnes denied any link between that fact and his work for GTECH.

Attorneys for Mr. Littwin also sought to depose Ms. Miers about the firing, but she resisted and a federal magistrate granted her motion to quash the subpoena.

Weeks later, the lawsuit was settled. GTECH agreed to pay Mr. Littwin $300,000 to settle his claims that the company illegally interfered with his employment.

Ms. Miers, who was at one point hired byMr.Bush to seek out records that could hurt his presidential bid, was never formally questioned about Mr. Littwin’s firing or the allegations of impropriety surrounding the GTECH contract. Neither she nor the lottery board was ever named as a defendant in the case.

On the advice of his attorneys, Mr. Littwin will not grant interviews about the episode, but he seems eager to share his story with the senators who will vet Ms. Miers’s nomination. “I have an agreement in my contract where I can’t discuss it. However, if they subpoena me, I’ll testify,” he said.

The FBI has reportedly contacted Mr. Littwin’s lawyers in recent days. A spokesman for the ranking Democrat on the Senate Judiciary Committee, Senator Leahy of Vermont, said Senate staffers plan to explore all aspects of Ms. Miers’s work record.

As conservative opposition to Ms. Miers’s nomination has grown, there have been indications that some Republicans may seek to explore Mr. Littwin’s story. In recent days, his account has been discussed on conservative Web sites that rarely feature stories critical of the Bush administration.

The White House has declined to respond to Mr. Littwin’s allegations, but colleagues who served on the lottery board with Ms. Miers deny she was involved in any wrongdoing.

“Everything she did as far as I’m concerned was done in a very positive, justifiable manner,” a former lottery commissioner and chief justice of the Texas Supreme Court, John Hill Jr., said.

“She really brought some very tough-minded leadership,” another ex-commissioner, Elizabeth Whitaker, said, adding that Ms. Miers’s ethics were “unquestioned.”

A spokesman for GTECH, which has endured a series of ethics-related scandals separate from the Texas case, said the firm has no desire to discuss Mr. Littwin’s allegations. “The company was reorganized. The people were involved in Texas are no longer with the company, by and large,” the spokesman, Robert Vincent, said.

Mr. Littwin now passes his days as an ombudsman for nursing home residents as a volunteer for a nonprofit agency that advocates on behalf of handicapped children. He shows little trepidation about the roller-coaster ride he will face if the Senate decides to pursue his claims. “I’m coming, if they subpoena me,” he said.