The well-oiled Kennedy campaign machine got rolling last week in this fashion:

In New York Thursday night, the Secret Service, assigned to protect Sen. Edward M. Kennedy (D-Mass.), managed to lose the senator's luggage, and with it the tuxedo he was to wear to a dinner of the Investment Association of New York. Kennedy finally showed up at the dinner, in a business suit, roughly 30 minutes late.

Friday morning, Kennedy's motorcade to the airport found its way blocked by several New York fire trucks. A member of the campaign entourage rushed back to the press bus to announce that Kennedy was going ahead alone, that the press bus was on its own and good luck to all. The press bus made it to the airport in time for Kennedy's scheduled departure. The senator did not.

Friday night in Boston, Kennedy sat at a table at the dinner of the Massachusetts Bar Association for the usual rousing introduction before a home audience. It was presumably rousing, but no one on the fringes of the room could be sure. The sound system had broken down.

These are the normal foulups that bedevil any beginning campaign and, if nothing else, the first trip out of Washington by the Massachusetts Democrat since he sent his well-publicized "signals" of presidential intentions proved that not even a Kennedy is immune.

Kennedy is living now in a curious kind of political twilight zone. He is all but an officially declared candidate. He certainly travels as an announced candidate, or even a front-runner, what with the numerous aides around to assist and the press contingent large enough to require a bus.

But he is not exactly, officially, in the race yet, and that leaves him in a position of luxurious flexibility.

The issue that is impelling him toward a challenge to President Carter, Kennedy said on the two-day trip that ended here Saturday, is the state of the U.S. economy. By design or not, he delivered that message to two audiences that are at opposite ends of most economic arguments and that -- for different reasons -- did not seem to care that he offered nothing in the way of solutions.

It was two different worlds into which Kennedy traveled in his brief foray. One was a plush ballroom of the Waldorf-Astoria hotel, where Kennedy, champion of government deregulation, sought to assure his elegantly dressed audience that he is not bent on turning the economy upside down.

"We are making a clean break with the New Deal and even the 1960s," he said. "We reject the idea that government knows best across the board, that public planning in inherently superior or more effective than private action.There is now a growing consenus, which I share, that government intervention in the economy should come only as a last resort, when market forces fail to meet important needs such as the protection of public health and safety."

The investment executives liked those lines but, perhaps feeling the effects of the lengthy cocktail party that preceded the dinner, grew progressively distracted and restless as Kennedy expressed his devotion to free enterprise. The senator finally junked the concluding portion of his speech and ended his remarks abruptly.

The next day in Boston, Kennedy found himself in a noisy, smoke-filled meeting room of the aging Park Plaza hotel, where hundreds of members of the Massachusetts AFL-CIO chanted, "We want Ted." Here it was Kennedy the champion of the working class, railing against the "unconscionable" profits of the oil companies, which he blamed on Carter's decision to decontrol domestic oil prices.

In neither speech did the senator set out proposals to deal with the economic ills he sees, nor did he suggest how he would try to reconcile the stockbrokers' interest in increasing profits to spur investment and the trade unions' outrage at the price of home heating oil in New England.

For the moment, neither the skepticism of the New York audience nor the faith of the crowd in Boston demands much more than the generalities that Kennedy is offering. But that will change quickly as he moves toward an open challenge to the president, when he will have to begin making specific choices on economic and energy policy.

Sorting out those choices, finding the political ground from which to challenge Carter's management of the economy, could prove more difficult than learning how to beat the press bus to the airport.