S.I. Hayakawa was the comic relief of the 1976 election campaign, the candidate who said what came into his head and who proclaimed that we should keep the Panama Canal because "we stole it fair and square." Californians laughed all the way to the polls, where they elected Hayakawa to replace Sen. John V. Tunney.

Now, as a 70-year-old freshman senator, Hayakawa has them laughing again. In his first weeks in office he has surprised his colleagues by leaving the presidential inauguration because his feet were cold, enlivening a dull Republican gathering by playing the harmonica and dancing with a blonde secretary, and startling a non-partisan group of partygoers by telling them how to create a Republican majority.

Behind the unconventionality, however, there have been early signs that in the Senate Hayakawa does not intend to play role of court jester of the Republican right.

Ignoring the spate of jokes about him - many of which center on his admitted preference for an afternoon nap, even if it occurs during a hearing - Hayakawa has concentrated on sensibly and methodically learning the business of the Senate. When he has mastered an issue, he expresses himself with the grace and precision of the serhanticies he is. None of this should be surprising who has examined Hayakawa acceptable career.

On the Panama Canal issue, for instances, Hayakawa has without announcement retreated from his campaign position of opposing negotiation with Panama leading toward a new treaty.

"The United States entered negotiations with panama to establish a more modern ad martually acceptable relationship between our two countries than the [WORD ILLEGIBLE] treaty provides," declares a form letter sent out by Hayakawa to constituents writing him on the issue. "Moreover, failure to enter such negotiations could well affect not only our friendly relations with Panama but with the rest of Latin America.

Hayakawa's latter goes on to say that a new treaty should provide for access through the canal for the United States and defense rights. But he tactly accepts Panamanian ownership if these conditions are met, a position anathema to many conservatives.

There have been other signs that Hayakawa cannot easily be fitted into ideological mold. He opposed the nomination of Griffin B. Bell for Attorney General, believing that Bell was "almost too much a man of his place and time and limited by that fact rather than being a national figure."

He pressed repeatedly for the pardon of Iva Toguri D'Aquino, known to World War II veterans as "Tokyo Rose," and is credited by a least one former White House aide with having played an influential role in President Ford's decision to grant that pardon. Despite his age, Hayakawa was one of four senators to support a Senate reorganization report that would have eliminated the Select Committee on Aging on grounds its work could easily be done by another committee.

"I am reminded of some things I learned from my radical students at San Francisco State in the 1960s," Hayakawa said in support of eliminating the committee. "There kept telling me that inefficient and inequitles in human institutions continue to exist because of influential people who stubbornly hang on to the exsting system that gives them their power and influence. As an alleged conservative Republican, I find myself perculiar on the side of those pushing for change right now."

One change that Hayakawa is pushing foe is-thoroughly predictable on the basis of his 1976 champaign. He has called for allow young persons to work for 38 per cent less than the minimum wage, and has introduced an amendment to youth employment legislation that would allow such an exemption for persons under 18. Not even Hayakawa contends that this amendment has much of a chance in the present section.

California's senior senator, Democratic ship, Alan Cranston, has established a cordial relationship with Hayakawa. Cranston believed that "sensible conservatives" in California already realise that Hayakawa is not one of their own.

"He's unpredictable and will cast a lot of good votes and a lot of bad votds," predicts Cranston. "I don't know how it will add up, but it's great to have a senator who's individualistic and different."

In one sense Hayakawa's political career demonstrates the shallowness of political labels," The Canadian-born Hayakawa, prohibited by U.S. law from becoming an American citizen until 1984, cast his first presidential vote for Adlai; Stevenson in 1956, and he remained a Democrat until 1973.

During most of his life Hayakawa was considered a "liberal," largely on the strength of his widely used 1841 book, "Language in Action." Hayakawa wrote the book as a response to the success of Hitler and his propaguada, and he used it to expose the fallacies of Nazi anti-Semitism and the danger of stereotypes.

But Hayakawa become typesas a "conservative" in 1968 and 1969 when, as president of San Francisco State College, he resisted demonstrators. Overnight after an incident in which he ripped out the wires of a student radicals loudspeaker, Hayakawa became a California media celebrity.

The image persisted long enough for Hayakawa to win the 1976 Republican senatorial primary, where he was lightly regarded by his two principal opponents, Robert H. Finch and Rep. Alphonso Bell. But Bell and Finch split enough votes between them for Hayakawa to win.

So he came out of the primary regarded as a "lucky" candidate, as he has been considered lucky all his life. He was at first a decided underdogagainst Tunney.

"There is no way for Hayakawa to win this election but he's going to," said Ronald Reagan aide Lyn Nofziger several weeks before the election. Some of Tunney's people couldn't believe it even the votes were counted.

Lucky? Maybe.He was an obscure professor of English who gained public recognition by writing eight books. He became an expert tennis player, a swimmer, a fencer and a jazz authority, once writing a jazz column for the black newspaper, the Chicago Defender. He married a Caucasian woman when such marriages were not recognized by the law in California and stoically endured the prejudices such a marriage then involved.

his golleagues, at the University of Chicago and San Francisco State College formed differing opinions of him. Some found him fun to be around, others thought him remote and egotistical. All agreed that he was a remarkably disciplined man who made a point of doing well what he set out to do. .

"Whatever he does totally absorbs him while he is doing it, says a colleague from his San Francisco State teaching days. "When he is flashing, fishing if only thing that interests him. When he is listening to jazz or playing as instrument, nothing else intrudes."

Discipline would seem to be the key to Hayakawa's personality. He relentlessly celebrates to work ethic and the values of those who sacrifice to get ahead. His view that man can make something of himself, whatever the racial or economic barriers, has framed his political views, which amount basically to a near-deification of the middle class.

"If I became a popular hero it is because I was seen as a person who stood for the middle-class values and if people flocked to the Republican banner at that time it is because they felt that the Repbublican Party was the party where middle-class values were really cherished more than they were in the Democratic Party, Hayakawa said at a recent meeting of the Republican State Central Committee in California.

While Hayakawa's friends and staff members describe him as warm and friendly, this is not the side usually seen in public. In conversation he is abrupt and laconic. He can be discursive on scholarly points, always in academic sentences studded with "almost" and "perhaps," and he breaks into a direct or profane response only when confronted with a question he does not care for.

When Hayakawa was asked during the election campaign about an initiative on the California ballot to permit greyhound racing, he replied: "I don't give a good goddamn about greyhounds, one way or the other. I can't think of anything that interests me less."

But he has a sure media sense. For one thing he knows the value of symbols to the media, and he has made his own favorite symbol, the tam o'shanter he wore during the San Francisco State disorders, the banner and reminder of his stand.

He also knows that reporters tend to rally to the side of the underdog. Recently, Hayakawa spent 45 minutes on the telephone with an Oakland tire operator whose one-employee shop was being picketed by the Teamsters union.

"I thought they should pick on somebody their own size," said Hayakawa.

The coverage of this seemingly random phone call made Hayakawa a defender of the underdog in his home state. He won added plaudits a few days later when he persuaded a Vietnam war hero who wanted to give his medals back because of President Carter's pardon for draft evaders to instead come into his Senate office and talk about his feelings. Before he left, with his medals still with him, the Vietnam veteran had been photographed in a tam o'shanter with Hayakawa.

Hayakawa hardly seems a media wizard as he bounces through the Capitol corridors. At 5'6" he shares with Sen. John Tower of Texas the distinction of being the shortest senator. Even though Hayakawa dresses distinctively in bright plaid sports jackets, he is frequently confused with the two other senators of Japanese ancestry, both of whom are from Hawaii.

Hayakawa does not seem to care. He seems oblivious at times to events around him, living, as an aide puts it, "in a world of his own." At other times he will stare in childlike fascination at a painting or the Senate subway cars. When Hayakawa attended the winter meeting of the California State Society, an affair that is by tradition strictly social and nonpartisan, he startled his largely Democratic audience with a detailed speech on how to create a Republican majority. Hayakawa said afterward that an aide had told him the meeting was a Republican event.

But Hayakawa has always been a serious person - "far more serious than he appears," observes Cranston - and those who have known him for a time believe that his gaffes and his difficulties will be a passing phase because Hayakawa will not be content to be a Senate joke.

"I must say I'm overwhelmed by the responsibility of being a senator," Hayakawa said last week. "It really is one hell of a big job and it demands the best of me. I'm sorry that there isn't time to give matters the attention they deserve. It's the hardest work I've ever done in my life."