The key-note address was a firm of a speech by Hubert H. Humphrey given just before his death. The most popular button -- used to raise funds for legislative candidates -- featured a picture of Harry Truman. When the Iowa Democratic Convention was four hours old, an American ambassador, home from his African post to visit his politician brother, asked wonderingly, "When do you suppose we're going to hear Carter's or Kennedy's name mentioned?"

That's the way it was here Saturday, as the Iowa Democrats, using nostalgia to blur the bleak realities of the moment, completed the delegate-selection process that began in a fever of excitement last January.

Then, it seemed the whole world was watching the first round in the struggle between President Carter and Sen. Edward M. Kennedy (D-Mass.) for the Democratic nomination. All three networks sent their anchormen to Des Moines as record numbers of voters flooded the precinct caucuses to give Carter his victory.

Saturday, only a single network correspondent showed up, and he left as soon as Sen. John Culver, the subject of his story, finished speaking -- 12 hours before the final 16 of Iowa's 50 delegates were elected. On the floor of Veterans Memorial Auditorium, more than 750 of the 3,200 delegate seats were empty -- no-shows bored by the final act in the drama.

The results were pre-scripted. Carter, who had beaten Kennedy by a 3 to 2 ratio back on Jan. 21, who 10 of the 16 at-large delegates elected to complete a lineup of 31 Carter, 17 Kennedy, and 2 uncommitted. Carter supporters also won two of the three national committee posts, with the third going to Chuck Gifford, a pro-Kennedy United Auto Workers official, as a gesture of unity.

There was almost none of the effort Kennedy's national headquarters had promised in this post-primary period to persuade uncommitted or "soft" Carter delegates to switch. No members of Kennedy's national staff even bothered to appear, and a post-midnight motion to send all the Iowa delegates to New York uncommitted was defeated after desultory debate.

Bill Romjue, who organized the state for Carter last winter, came back in a formal business suit. Having worked in a dozen other states since Iowa, Romjue was having trouble remembering the names of some of the local Carter workers who came up to him. "No," he told them, "I don't think I'll be back in the fall -- I'm slated for Virginia.

"When the Carter and Kennedy organizations pulled out after the precinct caucuses, they left a huge vacuum," said John Law, the executive director of the party. "It's been very quiet," agreed state chairman Ed Campbell. "It's a little scary."

When the cameras turned away, and the sharp competition of January ended, it seems that a good deal of the Iowa Democrats' optimism and sense of mission evaporated. The latest Iowa Poll of the Des Moines Register and Tribune, taken a month ago, showed Carter in a remarkably competitive position in a state that has gone Democratic for president only three times in this century.

It had Ronald Reagan at 34 percent, Carter at 32, John B. Anderson at 19, and 15 percent undecided. But the talk in the convention was much gloomier than the results of the poll.

"We are in real trouble," said Dagmar Vidal, the state's pro-Carter retiring national committeewoman. "We could lose it all."

"It will be tough," Ed Campbell agreed.

Some of the fear stems from the Republicans, who presented a picture of unity and enthusiasm at their state convention, which Reagan addressed a week ago. Having lost Sen. Dick Clark two years ago, Iowa Democrats fear for Culver's future, whose challenger, Rep. Charles Grassley, was running nine points ahead of Culver in the Iowa Poll even before Grassley won an unexpectedly big victory over a wealthy moderate opponent in the June 3 primary.

But some of the problem stems from queasiness about their own ticket. "We've got a double negative," said Floyd Gillotti, a colorful veteran of South Des Moines politics and Carter supporter. "Kennedy could not even become the symbol of the anti-Carter sentiment that's out there, but Carter was so weak he couldn't get rid of his challenger until June, not even as an incumbent."

There are some enthusiastic Carter backers. Roger Johnson, a chemist in Belmond who doubles as the Lake County chairman, carries around a frayed contribution check he sent Carter May 13, 1975. As far as he is concerned, Carter is "a very smart and analytical man, who has not looked for the easy solutions but has handled the tough problems as well as anyone could. He represents the belief in family and freedom of worship that we in small-town, rural America value."

David Garst, a Carter fund raiser, agrees, and blames "the media" for all of Carter's troubles. But after several hours in the convention hall, he said of the unenthusiastic delegates, "I'm not sure Carter could carry this crowd by much" against Reagan and Anderson. n

John McCormally, the Iowa editor credited by the president with being his first out-of-state editorial endorser in 1975, noted that "the Carter people are spending an awful lot of time apologizing for him."

Examples were easy to find among Carter delegates like Maria Houser of Iowa City, who said, "I'm really beginning to waver for Anderson. It's getting almost embarrassing to be for Carter, because people say he's a turkey, that he can't do anything right . . . I mean, sending the helicopters to Iran without sand screens!"

Among the Kennedy delegates, the disaffection was even more evident. Herman Wrice of Atlantic, one of the few blacks at the convention, said he worked for Carter in 1967 "on the strength of Andy Young's support." But he said, "He's broken too many promises to us. Those bottles they threw at him in Miami the other day were very significant. I'll campaign for Anderson this fall. I don't feel that's a wasted vote. Carter's the waste."

Beverly Trost of Waterloo, one of the original members of the Iowa Draft-Kennedy Committee, came to the convention with a button reading: "Anderson-Mondale. Why not the best?"

"I'll tell you exactly what will happen this fall," she said. "I'm going to vote for Anderson, the state is going for Reagan and Chuck Grassley is going to be our senator. The Republicans are coming home in droves and all the little blue-collar workers who are getting laid off are going to blame it on the right person -- Jimmy Carter."

But her fellow townsman, machinists union official Russ Woodrick, while equally pro-Kennedy, is not shutting the door on Carter.

"Anderson is just another Republican vote as far as his labor record is concerned,' Woodrick said, "and if it comes down to Carter or Reagan, obviously I will support Carter. Somebody is going to be naming people to the Supreme Court, and I'd a lot rather it was Carter than Reagan."

Asked about the threats of many other Kennedy delegates to bolt, Woodrick said, "Remember, it's June, not November."

And considering how different June is Iowa from January, that is a point worth remembering.