Massachusetts is already following the Federal Government's example. Just as the Government gave up on universal national health insurance after President Clinton's plan failed in 1994, and moved toward piecemeal changes, Massachusetts lowered its sights last year.

Abandoning its grand hopes of health insurance for nearly all its residents, to be provided largely by employers, the state decided to seek some health insurance coverage for everyone under 18 -- financed by a 25-cent-a-pack increase in the cigarette tax. The increase raised the state tax on cigarettes to 76 cents a pack; the price of cigarettes is now $2.31 to $2.86 a pack.

It was a tough legislative fight, even in a state known for generous public services, with the proponents overcoming a veto by Gov. William F. Weld, who opposed any new taxes.

Now the state's United States Senators, Edward M. Kennedy and John Kerry, want to take the Massachusetts approach national, with a tax increase on cigarettes that could reach 75 cents a pack or more. They contend that smokers and the tobacco industry can afford the cost of health insurance for the 10 million children who now have none, and that teen-age smoking will be discouraged in the process.

Senator Kennedy said early in February that uninsured children were rarely treated for chronic problems like earaches and asthma.

''We should make sure the sons and daughters of working families get a healthy start,'' he said. ''The best way to fund this is a tax on tobacco, which causes five million premature deaths a year and weighs down our whole health system.''

Their approach is one of several being talked about in Congress, where the President's proposal to expand coverage gradually so that half of the 10 million children not covered now will be insured by 2000 has been widely criticized, especially by Democrats, as inadequate.

The children's health issue is gathering steam among Republicans, too. Mr. Kennedy, a Democrat whose career is marked with bipartisan successes despite his liberal reputation, said that a bill he was proposing drew ''very serious'' interest from four Senate Republicans and several young House Republicans.

Representative Bill Thomas, a California Republican who heads the Health Subcommittee of the Ways and Means Committee, said in early February that he would soon hold hearings to get a sense of the scope of the problem.

In Massachusetts, there was political appeal to taxing tobacco to help children. Judy Meredith, who led the lobbying effort for the bill, said it was a pleasure to promote ''a tax on an industry that everyone thought were bums, marketing a poisonous material.''

Still, as Geri Denterlein, who led the public relations effort, put it, Governor Weld, a Republican, fought hard and ''it wasn't a lay-down hand.''

Tobacco lobbyists were omnipresent at the Statehouse, and tobacco companies funneled thousands of telephone calls from protesting smokers to their legislators. Still, the obstacles were nothing like those in Washington.

Not only is the tobacco lobby one of the biggest donors in the nation's capital -- Philip Morris alone invested $3,162,939 in the Republican Party and its candidates in 1995 and 1996, and $739,216 in the Democratic Party -- but also, Republican resistance to any new taxes is intense.

In Boston, State Representative John E. McDonough, the Democrat who wrote last year's legislation, said: ''A cigarette tax, to most people, is not a tax. You won't find any other tax that people will come out and say, 'We like that tax; raise it some more.' ''

But in Washington, Representative Bill Archer, the Texas Republican who is chairman of the House Ways and Means Committee, said that while he would be happy to discourage smoking and help children if they need it, ''a tax increase as far as I am concerned is a tax increase, and we have taken a very firm position against tax increases.''

Using the tobacco money, Massachusetts expanded both its Medicaid program and the Children's Medical Security Plan, which began in 1993 by covering children under 7. Medicaid, paid for in significant part with Federal dollars, will now cover everyone up to 133 percent of the poverty level, or all families of four with incomes up to $20,748 a year.

The Children's Medical Security Plan is providing a somewhat less generous insurance package than Medicaid -- more limited mental health and prescription drugs and no tonsillectomies, in particular. For families with incomes of less than $31,200 a year -- 200 percent of poverty -- the coverage is free, and the co-payment $1 per doctor's visit.

For families with incomes of $31,200 to $62,400, the charge is $10.50 per child a month, and the co-payment $3. Above that level, the charges are $52.50 a month and $5 a visit.

The program, administered for the state by the John Hancock Mutual Life Insurance Company at a charge of $10.50 a month for each child, allows parents to take their children to any doctor in the state, although some doctors bill them for what the state does not pay.

David H. Mulligan, the Massachusetts Health Commissioner, said that while uninsured children had always got emergency room treatment, this program was adding ''routine medical visits, check on immunizations and tests for lead poisoning.''

And since the expansion raised the eligibility age to 18, doctors are providing a new range of guidance to patients on questions like ''drugs, alcohol, teen sexuality, violence -- that band of issues.''

Of this state's approximately 150,000 uninsured children, about 60,000 will be covered through the expansion of Medicaid. The expanded Children's Medical Security Plan program may reach 40,000 to 60,000 more. It has enrolled about 7,000 more children since the expansion took effect in November.

Mr. Mulligan said it was hard for the state to ''market'' what he acknowledged was a ''hodgepodge'' of health programs. In one innovation, applications for the Children's Medical Security Plan have been sent home with report cards.

While Mr. Mulligan tries to expand coverage, the coalition of supporters that prevailed here hope to replicate the campaign elsewhere.

In Massachusetts, Mr. McDonough said, data showing support for paying for children's health with cigarette tax increases ''gave legislators a comfort level so they would know that what they were facing on the phones was a very small minority of their voters.''

In Washington, Marian Wright Edelman, head of the Children's Defense Fund, said, ''We would really, really urge states not to wait for the Federal Government, but to go forward.''

At the same time, Ms. Edelman called for Congressional action and termed Mr. Clinton's proposal inadequate. ''This is a solvable problem,'' she said, ''and it is absolutely outrageous that the world's leader in health technology leaves 10 million children uncovered.''