The Gridiron Club dinner was not Nelson Rockefeller's kind of scene-- a bunch of journalists and government biggies spending a whole evening cracking jokes.

"His idea of a great evening was to talk about municipal bond issues or de'tente with Henry Kissinger," says Joseph Persico, who has just translated the 11 years he was chief speech writer for Rockefeller into a biography entitled "The Imperial Rockefeller."

Nevertheless, Rockefeller not only had to go, but to speak. And he had to be funny--the unwritten law governing Gridiron dinners.

"So I got hold of Robert Orben, the comedy writer," Persico recalls.

Orben supplied some sure-fire shtick about, among other things, Rockefeller's money.

"He killed just about all of them. Jokes about the money were not allowed."

So Robert Strauss, representing the Democrats, stood up and said, as Persico tells it: "I want you all to know--party differences aside--that I like Nelson Rockefeller. And I'm going to tell you why. I like Nelson Rockefeller . . . because he's got MOOOO . . . NNNEEY!"

When Rockefeller spoke, he came to a joke about Robert Strauss in his script. He stopped, and said: "You know, I just wish Bob had said he liked me because I was real."

He is very real to Persico.

"When he died I almost felt as if a weight had been removed from me," says Persico. "You felt his presence --he made you feel as if you had an obligation to him. . . ." Persico, who is sitting at a cafeteria table, looks away from his Coca-Cola, as if Rocky might be coming up behind him. He frets. He marvels. "I've got to stop talking about it, I can feel it. I can still feel it."

Nelson Rockefeller was the man who would be president and maybe should have been, given the competition that beat him out. It was one of the few ends that was commensurate with his beginnings. He was a prince of Pocantico, an earl of the Empire State, the grandson of John D. himself, who was worth $900 million when Nelson was born in 1908 --when $900 million was worth $900 million.

Smart. Energetic. Self-disciplined --he overcame dyslexia, a reading problem, with sheer effort and graduated from Dartmouth with a Phi Beta Kappa key. Ambitious. A wheeler-dealer who would tolerate no obstacle to his ambitions, who didn't even see the obstacles that stymie the rest of us.

When he was vice president, he read a newspaper article about the financial strain Greenland was causing Denmark. He sent the clipping to an aide with the note: "Why don't we look into buying it?"

Once, according to Persico, New York State Republican chairman Dick Rosenbaum was riding in Rockefeller's jet over the Dakotas. He looked out the window and saw something familiar in the dusk. Rockefeller informed him it was the presidential faces carved into Mount Rushmore, and asked if he wanted a better look. He had the plane turn, then picked up the phone, and Rosenbaum looked down to see the floodlights go on for a private viewing. Rosenbaum later told Persico: "When I'm flying with him, I always feel safe, you know, as though nothing would be permitted to go wrong with the plane."

Generally, Rockefeller did not have the knack, like Churchill or Kennedy, of inspiring anecdotes, Persico says. His breakup with his first wife in 1961 made headlines, and scandal hovered around his death in 1979 in the company of a young woman named Megan Marshack, but otherwise there was comparatively little gossip, trivia or apocrypha. He didn't even have nicknames, except for "Rocky."

"What you'd hear would be somebody coming out of his office and they'd say, 'I just had a meeting with The Great Conceptualizer,' or 'I just went over the budget with The Nation's Leading Fiscal Authority,' " Persico recalls. "You were always wrong in a debate with him. It was demeaning. It was corrosive. He had to show you he knew more about your subject than you did. It was egomaniacal. I don't know of anyone who actively disliked him, but there was that invisible shield. There were mannerisms that tipped you off that to him you were a useful instrument."

Persico takes a moment to think of exactly what those mannerisms were. He is 51, a full-time writer living with his family in Bethesda. He worked his way up from a second generation Italian-American background in Gloversville, N.Y., a guy who couldn't believe that somebody with Nelson Rockefeller's background could be "smart and tough and hard. This was my first real shock," he says.

"He had a way of working with you on something at his desk," he says, "and when you were finished he wouldn't say you were finished, he'd just pick up his phone and say, 'Get me Bill Ronan,' or whomever he wanted to talk to next. He wouldn't even look at you. And you'd know it was time to back out of the office."

Did that hurt?

"Sure."

Persico says he set out to write a book "that shows this guy with the bark off. I also wanted to be able to look Happy Rockefeller's second wife and Laurance one of his three surviving brothers in the eye." He points out early in the book that none of Rockefeller's myriad staffers through the years has written about him. And he says now that "you have seen that Rockefellers pervade this country, that their tentacles are everywhere. Also, the Rockefellers are good employers, they take care of you. There was a sense among a lot of people close to the family, almost a question of, 'Is there life after the Rockefellers?' Writing this book is a declaration of independence."

Still, Rockefeller's power lingers in the back of Persico's mind--that sense of obligation. Maybe it's because Rockefeller believed everything that a poor Italian kid would want to believe about this country.

"He was almost touchingly naive --he believed in the merit system. He believed that if he could just be the best goddam governor of New York that there ever was, that then he'd get promoted to president. Then he saw people like Carter and Goldwater and McGovern get nominations, and slowly came the dawning, when it was too late. He said, 'I went the wrong route. I should have gone Carter's route--a full-time seduction of delegates.' "

He tried for the presidential nomination three times. There were plenty of political reasons to explain why he didn't get it--Rockefeller the liberal in a Republican party moving right, Rockefeller going up against Sen. Barry Goldwater in 1964, or the contempt he had for Richard Nixon or Ronald Reagan. Plus the scorn he may have had for the whole party. He once said to someone who asked the reasons for his failure to come away from the GOP convention a nominee: "Have you ever been to a Republican convention?"

Persico says the problem wasn't people resenting his money.

"People would be down on him. They'd say, 'That rich son of a bitch is spending our money.' But come election day, they'd say, 'We got dollar value,' and they'd vote for him."

The book is full of both the parsimonies and extravagances of the rich. In 1968, while campaigning in South Carolina for the Republican nomination, Rockefeller summoned his advance man and said he was worried about expenses. He pointed to the Oreo cookies that his staff was instructed to place next to his bed at every stop. He said: "Now I like Oreo cookies. But I only eat three or four. Here you've got two dozen. Can't we get a refund on packages we don't use?" From then on, uneaten Oreos were carried from stop to stop.

He once started to illustrate the effect of a tax measure by saying, "Take an average family with an income of a hundred thousand dollars." In a speech to the League of Women Voters he provoked three minutes of laughter when he plugged a no-fault auto insurance proposal by using himself as a hypothetical example. "Suppose I was injured in an automobile accident. And suppose my family had nothing to live on while I was out of work."

But he was great in crowds, pressing the flesh, as they say--kissing babies and eating hot dogs at Coney Island, flashing that long, thin grin and barking "Hiya fella!"

"If he'd been a Democrat, he would have been a second Roosevelt. But he was a rich man in the Republican Party. There was no irony."

There was no sense of tragedy, either. And there was relentless, mandated optimism. "Once I wrote a speech for him saying that blacks had only an X percentage of jobs that whites had, that kind of thing, and he changed it to say that blacks had now managed to win that same percentage. No negativism was allowed--he carried that to its outermost limits."

Rockefeller was consistent, rational and determined, with all the intuitive sense of people that marks good politicians. He had his quirks, but basically he was everything people wanted or expected him to be--aristocracy hard at work for the common good.

But no ironies, such as Roosevelt being a traitor to his class. Says Persico: "You remember when Jack Kennedy called the president of U.S. Steel a son of a bitch? Nelson Rockefeller couldn't have done that."

Nor would he have seen the humor, the ironies and the intrinsic fascination in a scene that Persico remembers as being both typical and quintessential.

"I went into his office and he was talking on two phones at once while he waved a draft of a speech I'd written. It was about garbage disposal, and he gave it to me and said I'd forgotten the stuff about tertiary treatment. Meanwhile he's talking Asian politics into one phone and art into the other. I realized that he had Henry Kissinger on one line and Thomas Hoving on the other and he was putting together a Chinese art show while talking about garbage with me."

He was the totally public man.

"The only time I ever saw him with his guard down was when his brother Winthrop died--he always felt that he'd contributed to Winthrop's unhappiness and drinking problems by treating him badly when they were boys. It's interesting--I know that the people who worked for Winthrop who became governor of Arkansas had genuine affection for him."

Rockefeller blamed his failure to get the Republican nomination on his lack of "sufficient singleness of purpose and sufficient ambition to put everything else aside to do just that."

But was there some chord that he never managed to strike in the electorate, too? He was the only governor of this century to be elected four times, but he ran as an underdog each time.

"If you're talking about mass affection, no," Persico says. "Rockefeller didn't arouse that."

Something missing. Persico may sum it up when he says: "In 11 years of close association with him, I never once heard Nelson give a deep, unrestrained belly laugh."