Richard Blumenthal, a former classmate at Harvard recalls, was "one of the few people to have finished his senior thesis two weeks in advance and sent it to a professional typist."

He was, his father says articulate "even in kindergarten." His resume, listing jobs on Capitol Hill and in the White House as well as the Supreme Court, is enough to make mere mortals weep with envy.

Now Richard Blumenthal, 34, U.S. attorney for Connecticut, has a new item to add to his resume: He is Attorney General Benjamin Civiletti's choice to investigate leaks to the press in the Abscam investigation.

Blumenthal seems to be someone whom the goddess success appears to have grabbed up in a vigorous bear hug from which he has refused to be released. He is handsome, in a clean-cut, wavy-haired way -- he looks rather like a Jewish Robert Redford in a suit and tie, and evidently has prompted a fair share of female hearts to flutter.

In his public role he is self-protectively cautious, the armor of a man who knows he is under scrutiny. The ground rules for the interview are firm: He will not discuss anything related to his current investigation.

He would appear to be many people's definition of Mr. Success, particularly the Washington breed. Check out some of these 14-karat entries on the golden resume: Harvard, magna cum laude; staff assistant in the White House at age 22; Yale Law Review editor; law check in the Supreme Court; administrative aide to Sen. Abraham Ribicoff, and U.S. attorney at age 31.

"I don't think about what I'm going to do next," he said in a recent interview. "I find it easy to rationalize postponement of hard and fast decisions."

Some people who know him think he wants to be president, or senator, or at least secretary of state. "He'll do the Irish dance," said one observer in Connecticut. "You know, he'll go from assistant secretary of the Navy or something, to assistant secretary of state, to high-paid Washington consultant when the other party is in power, then back as secretary of state."

It's a familiar Washington waltz, although whether it will be reflected on Blumenthal's ultimate resume is impossible to know. For all he knows, he said, he might go back into journalism, his first love. He edited his high school paper in the Bronx (it was private school), was elected editorial board chairman of the Harvard Crimson, and worked as a summer intern reporter and briefly as a foreign stringer for The Washington Post.

All of which adds to the curious irony of his current assignment -- finding out who leaked to the press about the Abscam investigation. Blumenthal, known among reporters in Connecticut for his cordial and cooperative relationship with the press, is now viewed by other reporters as the enemy.

At his first (and so far only) press conference here, the reporters, most of whom had been covering the Abscam story, descended on him like a pack of piranhas. Hadn't he leaked information about investigation to reporters in Connecticut? Hadn't he talked to Bob Woodward and Scott Armstrong in the course of their research on "The Brethren?"

He only told reporters what was proper, he said, and he was "uncooperative" with Woodward and Armstrong.

"He may go through some rough times," said his father, Martin, a businessman in New York who left his native Germany to escapt Hitler in 1935. "The exposure, that's good. But there might also be some hostility in your corner [the press], and he's the fellow they can attack best . . . Anyway, he took the job, and he'll have to do the best he can." Boy Wonder

Here are the positive things supporters say about Blumenthal: very intelligent, hard-working, a good boss, sensitive, a dedicated public servant, a man of principle.

And the negative views: overly ambitious, ice-water in his veins, a self-promotor, more concerned about his image in the press than anything else, and lacking in the experience that produces the best judgement.

Whether it's a fascination with someone who seems to be so perfect, or an underlying desire to locate the clay feet, one thing is clear: People love to talk about him.

"I don't think that anyone succeeds at anything without being ambitious," Blumenthal said. "I have worked hard for whatever success I've had, they haven't been thrust upon me. On the other hand I could walk away from a job or an honor if I wasn't consistent with my beliefs."

"He's the kind of person who pleases his elders," a former boss once said.

Yes, his father said, he always made good grades. At a time when scores of young people were rebelling against the establishment in various ways, Blumenthal was hopelessly straight. He is remembered by some Harvard classmates as being one of the few who had an interest in politics and "the system."

He wrote his thesis on an aspect of the federal antipoverty program, under a faculty advisor named Daniel Patrick Moynihan, who later used some of his thesis research in a book and also asked Blumenthal to join him on Nixon's White House staff.

"Dick Blumenthal is 23 and at the center of the world," wrote Hugh Sidey in a column in Life magazine in 1969 called "Patriot in the Basement."

"As any student of the presidency knows, that means he is under a star that will influence his life from now on. He lives there hungarily, bearing that special guilt of affluent postwar youth, a Harvard magna cum laude, Phi Beta Kappa, 100-yard freestyler in 51.0 square jaw, burning eyes, mannered and muted."

While his contemporaries were protesting the war in Vietnam in the 1969 mobilization in Washington, Blumenthal was the man in the White House keeping track of the protest logistics.

He was detailed for a while to work with Donald Rumsfeld at the Office of Economic Opportunity, an association that led to his being proposed, at age 24, to head VISTA. For once, the golden touch wasn't there.

He was first mentioned for the job in January 1970. In April, he left the White House to join the Marines for six months of reserve training. In July, he was formally nominated by Rumsfeld. Two weeks later "sources" leaked a story that Blumenthal had turned down the job because he doubted the Nixon administration's commitment to the poor, and would not be able to such as the invasion of Cambodia.

Some people believed that the "sources" were Blumenthal himself, a charge he flatly denies. "I've never determined who leaked it," he said.

At any rate, the next day Blumenthal issued a careful retraction through the White House, that ran, in part: ". . . I personally believe that the Nixon adminstration has shown a commitment to ameliorating conditions of the poor . . .

"My recollection is that he made a judgment that [the job] wouldn't be in his best interests," said Rumsfeld, now the head of the G.D. Searle Co. i"My recollection is that he was very positive about what I was doing in O.E.O."

Rumsfeld said "I can't think of anyone better" for Blumenthal's current assignment, and that he is "one of the most talented people I've ever met." They keep in touch, he said, noting that he received a letter from Blumenthal just a few months ago. "He knows he could work for me any time," Rumsfeld added.

"The hardest thing he ever did was turn down the VISTA job," his brother David Blumenthal recalled. "He very much wanted to have it. I think he was being used. The Nixon adminstration -- remember, this was after the invasion of Cambodia when campuses across the country were exploding -- would have been delighted to have a young Democrat in that job." Convictions & Criticism

Blumenthal's appointment as U.S. attorney 2 1/2 years ago by the Carter adminstration was something of a surprise in Connecticut legal circles. He had been practicing law with a private firm for only nine months, and had no trial experience.

"He was frank about having no trail experience," said a former assistant U.S. attorney, Ray Sweigart, who was hired by Blumenthal's predecessor but stayed on until he, like most young attorneys, wanted to move into private practice. "He handled it very well. He relied on the assistants, but was sharp as a tack and an extremely hard worker."

One of the first changes Blumenthal made after taking office was to order that all press inquiries be handled by him rather than the assistants handling a specific case. This is not an uncommon practice among U.S. attorneys.

Following Justice Department policy, he shifted the focus of investigations and prosecutions to white-collar crime and consumer fraud, as opposed to the type of crime that could be handled by either state or local law enforcement, such as bank robbery.

According to the office's annual report for 1978 (the most recent figures available) of the 272 criminal cases handled, more than 90 percent resulted in convictions of one or more people, and non of the 13 cases that were appealed was overturned.

However, he has been criticized -- generally by people who do not wish to be named -- for judgements they feel a more experienced person would not have made and for "playing" to the press, assuring that he comes out favorably in the media.

In one corruption case for which his judgement is criticized, a Stamford, Conn., building official was charged with taking a $1,000 bribe; after the trial last month the jury deliberated about 25 minutes before acquitting him.

Blumenthal said the case was lost when the judge's instructions to the jury required them to consider whether or not the official had solicited the money, not just whether he had received it, in order to convict him under the statute under which he was being tried. Part of the government's evidence, he noted, included tape recordings indicating the man had received the money.

In another case, the defense attorney charged in court that Blumenthal had violated a pre-trial agreement -- a highly unusual accusation between defense and prosecution.

The case involved the Olin Corp., which pleaded no contest to charges of selling guns illegally to South Africa, and set up a $500,000 charitable fund as reparation. According to the transcript of the hearing, defense attorney Ira Grudberg charged that Blumenthal violated the agreement both had made by asking in court for additional punishment.

"There may have been a misunderstanding on Mr. Grudberg's part as to the agreement between the government and the defendant," Blumenthal said. "Such misunderstandings do occur."

Grudberg also felt upset, evidently, that someone had told the television crews and newspaper reporters to show up on the day the indictments were handed down.

A former assistant, Lawrence Herrmann, who was fired less than a year after Blumenthal took over, charged recently that his former boss refused to remove himself from an investigation in which he might have been called as a witness. The investigation involved the Stamford Democratic Committee, of which Blumenthal was treasurer for about nine months.

Herrmann said that a subpoena had been issued but not delivered for the Stamford committee's records, and that he showed this subponena to Blumenthal and asked him to disqualify himself from supervising the investigation. However, a man that Herrmann said could corroborate this charge, assistant U.S. Attorney Harold Damelin, said he had "no recollection of discussing an investigation of the Stamford Democratic Committee," nor any plans to subpoena the records.

Blumenthal said that Herrmann's charges are "completely false," and noted that there is no need to subpoena party records because they are filed as public record with the state.

In general, one observer said Blumenthal should be credited for prosecuting tougher cases than his predecessor, but faulted for some errors in judgment. Commuting Jogger

Blumenthal has been in Washington for about six weeks working on the leak investigation, which could last for months. He has been living about four days a week in a hotel near the Mall, convenient for jogging. On the weekends he commutes to his home in Stamford where he catches up on U.S. attorney chores. He denies that he is a workaholic.

His father and other friends lament that he hasn't found the "right girl" to settle down and marry. "He loves children," said his father, "I think he'd be happier if he were married."

Few people who know him have any doubt that he will successfully navigate his sensitive assignment in Washington and will return to take on other jobs and have more stories written about him.

He said he hasn't written any poetry for quite a while. He keeps a diary, but it's not quite the same thing.

He is asking what story he'd like to be covering, if, as he'd once planned, he were now a reporter.

"Ah, er," he said, with a hint of a smile. "I'd better not say."