Sharp organization is no longer essential and surrogates need not apply. Campaign 1980 is about the candidates now. And Sen. Edward Kennedy is building a comeback in Pennsylvania on a new foundation of reluctant voters.

They are not the squealers, not the bumper-strip bearers, not even the quietly committed. The uncertainty of events in Iran and the public disinclination toward President Carter and Kennedy have produced a situation that has the polls fluctuating, and the pols using phrases like "highly fluid." t

"Lesser-of-two-evils" has become the interviewers' coin of the realm. And it is in the midst of all this that Kennedy, running in an open field, has made up a lot of ground in this major industrial state that will hold its presidential primary tomorrow.

He has done it largely with people like T. R. Weaver.

The Pennsylvania primary is unfolding, in one act, in the ballroom of the Pittsburgh Hilton, at the state convention of the AFL-CIO. On stage, Kennedy, the challenger who is forced to function as his own surrogate, is pressing all of the buttons that have been the touchstones of Democratic politics for almost a half century.

Four rows from the back, T. R. Weaver, the conductor on the daily Pittsburgh & Shawmut coal run, is making up his mind.

He listens to Kennedy shout aganst inflation, against high interest rates, against budget cuts. Just the day before, he had heard Vice President Mondale defend the Carter record in a surrogate performance that won only rstrained applause. Now, as Kennedy exits to a mostly standing ovation, Weaver remains seated.

He has come to a conclusion: "Kennedy talks a lot and says nothing. Carter just does nothing. So I'll go with Kennedy."

Kennedy has won another convert.

Weaver is the sort of reluctant voter who has enabled Kennedy to close a gap that only weeks ago seemed prohibitively wide.

Carter strategists fear that the president could lose Pennsylvania, and perhaps by a big margin. they also feel he could win, but that he cannot win big. Kennedy advisers say Carter is still ahead, but that Kennedy has a good chance to win.

The election could be determined by voter attitudes could be determined by a comment the president made the other day during a brief campaign visit to the White House map room -- a comment that surprised his advisers and upset his campaign strategists.

Near the end of an interview with Pennsylvania television reporters in the map room, after the subject of Iran had been dealt with and dismissed and then raised once more, the president began an answer by commenting that he prays "several times a day" for the return of the hostages.

He then went on to say that he has had "several reports lately" that the Ayatollah Ruhollah Khomeini will not release the hostages "until after the election year is over in the United States."

Carter's advisers were surprised that their leader would make such a statement publicly. There had been no group strategy session where the disemination of such a message was discussed, they say.

"This was strictly the president's own judgment," said one senior adviser.

Now, these advisers fear that the statement (which was denied by the ayatollah) will hurt Carter politically by adding to the frustration and despair that have already brought Carter political problems.

A wekk ago, a statewide poll taken for Philadelphia television station KYW, showed Carter leading Kennedy by 42 percent to 29 percent, with a whooping 29 percent undecided. The Kennedy campaign says its poll at that time showed Carter leading by 10 points, but also with a high undecided figure.

Carter's pollster, Patrick Caddell, who believes in weighting and adjusting the raw data to ascertain which way the undecideds really would vote, did a survey at about time and showed Kennedy leading Carter by 43 percent to 40 percent, with a much lower portion of undecideds.

Carter's people promptly leaked the results -- partly to cushion the public for a loss that now seemed possible, but mostly to try to focus attention away from the president and his economic and Iranian woes and to make Kennedy the issue again, as he was earlier in the year.

Making Kennedy the issue has become a major concern within the Carter campaign. After the New York and Connecticut primaries, Carter's media adviser, Gerald Rafshoon, had second thoughts about the way the president's media campaign had put his message across, in view of the trouncing Carter received in those two states.

Rafshoon decided to try another tack in radio and television spots. The result, now playing in Pennsylvania, is a series of person-on-the-street encounters in which those interviewed speak negatively about Kennedy:

"Ted Kennedy is a big spender. . . . He's too liberal. . . . Kennedy changes his mind too often. . . . I don't think he can deal with a crisis. . . . I don't believe him. . . . I don't trust him."

Back when Kennedy was so far behind that the polls and the pols were making it seem that he was in danger of being lapped on election day, the challenger began picking up ground by working the state like a ward heeler.

He made all the stops, hit all the television talks shows, honored all of the radio interview requests, and soon he was logging more air time than the local anchormen.

The Carter forces, meanwhile tied by the president's self-imposed embargo on campaigning, countered with their battalion of surrogates. Pennsylvania has seen Rosalynn and Mondale and Robert S. Strauss; Miss Lillian and Aunt Sissy and Chip; Cabinet secretaries from an alphabet's worth of agencies, and the Who's Who of the White House staff.

Carter advisers have complained that their camp's surrogates do not get the same media coverage as the other camp's candidate. But, on the rare occasions when their paths cross, it is clear that the public does not regard a candidate and a surrogate as equals.

That was clear when Kennedy followed Mondale into the AFL-CIO and won the battle of the applause meter. And it was clear last Thursday when Kennedy followed Rosalynn Carter at the Westmoreland County Democratic Dinner, in that coal and steel county just outside Pittsburgh.

The First Lady was greeted politely but not effusively. Her message was partly about how her husband is doing the best job possible under difficult circumstances. It was reminiscent of the campaign four years aog, when Pennsylvania handed her husband the nomination by giving him a decisive victory over the labor-supported candidate, Sen. Henry Jackson.

Since then, she recalled, "We've had hundreds of people from this state in the White House -- even in the very past few weeks."

Kennedy was greeted enthusiastically and was interrupted for applause as, once more, he hit all the traditional Democratic themes.

Kennedy has proposed two major remedies for current problems. His audience sat silently when he mentioned one of them, his plan for wage and price controls. And they never got to react to the second -- gas rationing -- because he did not mention it.

Yet Kennedy seemed to win converts among this audience, apparently not because they necessarily like his solutions, but they like the way he explained the problems.

Kennedy strategists concede that their candidate must win the Pennsylvania primary if he is to have a chance of wresting the Democratic nomination from Carter. But if Pennsylvania represents Kennedy's last real hope, it also epitomizes the enormous scope of his problem: He can capture Tuesday's election and still not come away a real winner.

The game now is about mathematics, and the Democratic Party's delegate apportioning formulas are working against Kennedy as he seeks to come from behind. Kennedy trails Carter by 871 delegates to 443 by the most conservative of all estimates -- that of the Kennedy campaign. A total of 1,666 delegate votes is needed to win the nomination.

Because of the delegate apportioning formulas, Kennedy could score a landslide victory in many of Pennsylvania's congressional districts that have even numbers of delegates, and still come away with only an even split in those delegates.

In a district that has six delegates, for example, a candidate could win the popular vote by a margin of 55 percent to 45 percent, and still get just three of the delegates -- with his opponent getting the other three.

This kind of arithmetic can make it difficult for Kennedy to pick up much ground in the delegate race, even with a strong victory in this state that will send 185 delegates to the Democratic National Convention in August.

The Carter campaign's political director, Tim Kraft, has taken to looking at tomorrow in terms of total delegates. Missouri has its caucuses the same day, and Kraft estimates that Carter will win most of that state's 77 delegates.

"We could lose Pennsylvania by five or 10 points and still come out with a net plus on total delegates for the day," Kraft said.

In Pennsylvania, Kennedy's prime source of strength is in liberal Philadelphia and its surrounding suburbs. Carter is strongest in the small towns and rural areas in the central part of the state. And both men seem to have sizable strength in Pittsburgh and its surrounding blue-collar, ethnic communities.

There are no clear advantages of support. Both candidates have strong segments of union support. Both have the endorsements of elected officials and celebrities. Pittsburgh's mayor is for Carter, Philadelphia's is for Kennedy. Carter has Muhammad Ali and Franco Harris, Kennedy has Dr. J. So it goes.

While both sides battle for the edge in Pittsburgh, Kennedy's chances for a convincing statewide win may come down to his ability to pile up a big majority in Philadelphia, where Carter's state campaign manager, Terry Straub, says he plans no big get-out-the-vote effort, for fear that he could wind up getting out Kennedy's vote most of all.

Concerns about personal character have been a barometer of Kennedy's election-day fate all year. But Carter officials say their polls show that Pennsylvanians do not appear to have as strong a concern about Kennedy's character or morality as did the voters in Illinois and Wisconsin.

This factor could be crucial among Pennsylvania's Catholic voters, who make up some 40 percent of the Democratic primary vote in this state. In Illinois and Wisconsin, Kennedy lost the Cathloic vote, while in New York and Connecticut he won with it.

In Pennsylvania, Kennedy may have ceased being the issue of 1980. At Wilkes-Barre, a few miles from the gravesite of Mary Jo Kopechne and the house in a Swiftwater suburb where her parents live, Kennedy drew a large crowd on a chilly day in the town square.

Those in the crowd who were interviewed did not seem to hold the death of the local girl against the candidate who stood there asking for their votes. As one woman, Stella Pienta, observed; "Everybody's got a skeleton in their closet."

EPILOGUE: A problem of lifestyle, personal or familial, is the herpes of politics; it always raises whispered questions and it never truly goes away.

It is the sort of thing that is always there, in people's minds, and it was there inferentially the night Rosalynn Carter addressed the Westmoreland County Democratic dinner, and talked about her husband and the Iranian crisis.

"I have been very close to him in the past three months -- as I have been for 33 years," she said. And later: "It [the crisis] never leaves his mind. I see him every day, every night at dinner -- he's worrying about the hostages."

Kennedy arrived just after Mrs. Carter left and, aided by a quick staff briefing, opened his speech by saying:

"I'm glad to be here to fill in for my wife, Joan."