NEW YORK (AP) _ With tears in her eyes, Marcia Callender told President Clinton about her fight with the health care system that ended Dec. 3, 1992, when her son died peacefully in his father's arms.

Sitting knee-to-knee with her at the cramped counter of the Future Diner on Sunday, Clinton put his hand on Callender's shoulder and gently rubbed her neck.

''No family should have their grief compounded and their economic misery reinforced by this kind of problem,'' he said later, holding a portable microphone in his left hand, Callender's quivering hands in his right.

Callender's son Matthew suffered from Hurlers Syndrome, a developmental disease requiring continuing medical treatment.

But the Queens family lost their insurance when Callender's husband lost his job. Because her son's condition was ''pre-existing,'' Mrs. Callender could not get her health insurance to cover it. She eventually resigned to care for her boy.

Her husband then took a low paying job, so the family could qualify for medical and Social Security disability for their son.

Clinton heard hers and other stories during a visit to the Future Diner, an old campaign haunt in the New York City borough of Queens.

Later that evening, the president attended two fund-raisers for New York Mayor David Dinkins in an effort to stave off an embarassing Democratic defeat.

The first, at the townhouse of Seagrams heir Edgar Bronfman Jr., included about 70 guests. Among them were New York Gov. Mario Cuomo and Sen. Daniel Patrick Moynihan, D-N.Y.

Following, at a $1,000-a-plate gala that was expected to raise $1 million, Clinton suggested that one reason Dinkins is in a tough campaign with former federal prosecutor Rudolph Guiliani is that some whites are reluctant to vote for blacks.

''Too many of us are still too unwilling to vote for people who are different than we are. This is not as simple as overt racism. ... It is this deep-seated reluctance we have against all our best judgment to reach out across these lines.''

Clinton told New Yorkers that a Democratic mayor is even more important when there is a Democrat in the White House. ''You really want ... someone who will be doing things that fit with what we're doing in Washington. Otherwise, why'd you vote for me in the first place.''

Earlier, Clinton told those who had gathered to talk about health at the diner, ''I just do not believe we have to go on for another year, or five years or 10 years being the only nation in the world that can't figure out how to get health care reform.''

It was the second time this month that the president met with people who wrote the White House with their health care tragedies, a strategy designed to win sympathy for his proposed overhaul.

The diner, site of a economic policy visit by Clinton during the heat of the New York primary last year, was packed with journalists and about 50 invited guests, mostly people who have written the White House.

Josephine Angevine of Manhasset told Clinton that her health care premiums will be $12,747 this year, a heavy burden on her and her employer. Reading from her letter, she said, ''I am afraid of losing my job.''

Clinton dropped the microphone in his lap and sighed. ''Wow,'' he said. ''Takes your breath away, doesn't it?''

Linda Haftel of New York said said her premiums have risen rapidly since she was diagnosed with multiple sclerosis, and she is afraid to stop working because no insurance company will cover her with the condition. Her doctor advised her not to tell her insurance company about the illness.

Clinton, who promises to forbid exclusions for such ''pre-existing conditions,'' pointed to her across the diner and said, ''Here she is, at the peak of her capacity to give to society, wondering if she has to lie to her insurance company. This is the only country in the world where you can lose your insurance because you need insurance.''

Clinton's plan, sure to undergo revisions, is designed to guarantee all Americans access to medical coverage by mid-1997. The health security card is a symbol of that promise. To reach the goal, there would be changes in the way virtually everyone gets coverage.

Employers would pay at least 80 percent of their workers' premiums, and employees would pay the rest. Small businesses and low-income workers could receive subsidies to help them pay their share.

Americans would choose among a variety of plans offered by regional health groups, with lower-cost options likely to be health maintenance organizations and higher premiums for plans in which people pick their doctors.

The event and a gala dinner the mayor were scheduled as part of a strong effort by the Democratic party to salvage Dinkins' re-election effort and set the stage for congressional elections next year.