It takes a finely tuned sense of the absurd to run for president, and Edward M. Kennedy proved he had that attribute today, managing to laugh his way through the most ignominious day yet of his ill-starred campaign.

Kennedy smiled wryly this morning when five officers of Harlem's Chamber of Commerce spent 40 minutes praising one another but never said a word about the last of the Kennedy brothers, who sat, virtually ignored, in the background waiting his turn to speak.

And he joked right along with the traveling reporters when his two-engine prop plane sat at LaGuardia airport waiting for a break in the weather while a giant blue-and-white Air Force Two whooshed Vice President Mondale away, right on schedule.

The candidate even chortled during a scary, sickening flight through the storm when the press corps started playing "The High and Mighty" on kazoos.

But the crowning moment of Kennedy's Day of Ignominy was when his plane finally landed here in Syracuse and the candidate, with his bedraggled entourage trooped out into a blustery downpour so that the TV crews could film the day's "visual" -- Kennedy was to be endorsed by the local congressman, James Hanley (D-N.Y.).

For 20 minutes Hanley shouted generalities into the rain, saying Kennedy was "offering an alternative for consideration" and "opening up the avenue for dialogue."

Finally, a reporter broke in to ask, "Mr. Hanley, are you going to vote for Sen. Kennedy?" Hanley spluttered, coughed, cleared his throat, and finally said, "I would have to say that I will keep that private."

While everybody else cracked up, Kennedy sauntered over, put his arm around Hanley's shoulder, and said, "You can tell these guys, Jim, they won't tell anybody."

Hanley took this as a signal to launch back into his speech. "The senator is a team player," he roared into the microphone, and by now Kennedy had joined the general laughter. "Come on, Jim, do the right thing, he said with a big smile. But Hanley kept on talking and ducked all questions.

"Well, Jim I think they've run out of film," Kennedy said and spun on his heel and trekked off through the puddles back to the plane.

The whole dreary day went that way for Kennedy, who woke up to find a New York Daily News poll that showed him trailing President Carter among the state's Democrats by almost 2 to 1. The poll suggested, too, that Kennedy's best issues weren't cutting. Fourty-four percent of those surveyed said they believed Carter is lying about his flip-flop on the Israel vote at the United Nations, a key Kennedy issue; but 83 percent said Carter's best asset is "high integrity."

But as Kennedy dealt with tepid crowds and turbulent weather, he continued to show the striking equanimity he has displayed through all the reverses his campaign has suffered.

This may explain why Kennedy, who clearly knows that his chances of beating Carter are now close to nil, continues to say that he will stay in the Democratic race right up to the convention.

"I'm comfortable with what I'm doing now," he said Thursday night. "I'm talking about issues that are important to me, that I think ought to be the heart of the Democratic Party. So I'll keep going."

And Kennedy's advisers, some of whom are openly deliberating whether the Kennedy campaign should be terminated, say that the candidate is determined to resist those suggestions, no matter whom they come from.

"Nobody in the party has given him any help when he was running," said a veteran Kennedy hand. "So when these senators and governors call up and say he should get out, he's going to say he doesn't owe them a thing."

To strengthen the suggestion that the Kennedy campaign will not end no matter what happens in the New York and Connecticut primaries Tuesday, the campaign today released a schedule that shows Kennedy campaigning for four days in Wisconsin next week and then going on to four fund-raisers in the West in mid-April.

Kennedy converted one of the day's bad moments into a media coup of sorts at the session in Harlem this morning.

A man in the audience, Judah Anderson, stood up, demanding to ask Kennedy a question. The senator said he'd be glad to reply, but then the Chamber of Commerce president jumped in and shouted down the questioner, saying the chamber's rules prohibit questioning a speaker.

While those two barked at each other, Kennedy wandered down into the audience. As a swarm of camera-men gathered round, he engaged the questioner in a lively conversation, which ended with the two men shaking hands in agreement on the proposition that Carter's budget cuts will be disastrous for blacks.