WASHINGTON, June 9 — No policy issue has bedeviled Senator Hillary Rodham Clinton more than health care. Ever since the collapse of her proposal for universal coverage in 1994, critics have used the issue as prime evidence in their case that she is, at heart, a big-government liberal with a zeal for social engineering.

But now, as Mrs. Clinton heads into her re-election campaign and a possible bid for the presidency, she is trying to recast the political disaster of 1994 as something else: as a badge of honor, as a symbol of lessons learned and, perhaps most significant, as invaluable preparation for dealing with the problems in the health care system today.

“A lot of people know that I was involved in health care back in ’93 and ’94, and I still have the scars to show for it,” Mrs. Clinton says in a new biographical film that she is showing on the campaign trail. After raising the topic in a recent speech, she added, “But it’s worth wading into again — and we’re going to have to.”

Mrs. Clinton’s approach to health care is strikingly different this time around, a measure of her evolution from an impatient agent of change to a cautious senator — and potential presidential contender — keenly attuned to the political center.

In 1994, she and President Bill Clinton insisted that anything short of universal coverage was unacceptable and proposed a vast overhaul of the health care system to provide it: a 1,342-page plan that drew withering fire from an array of interest groups and died in a Democratic Congress.

Today, her plans to expand coverage are tempered and incremental. Her first major goal appears to be universal health coverage for children, which she hopes to advance by expanding the State Children’s Health Insurance Program, or Schip, an existing federal program up for review in 2007.

“I have to do what the political reality permits me to do,” Mrs. Clinton said in a recent interview. She said that covering everyone remained her ultimate goal, but that Democrats would be fighting “a lot of rear-guard actions” as long as Republicans controlled Congress.

Mrs. Clinton has not pushed a comprehensive coverage plan in her first term in the Senate. As part of the Democratic minority, she says she has primarily focused on defending existing programs from cuts by conservatives.

She also continues to shy from the ultimate challenge: describing what a comprehensive Democratic health care plan would look like. When pressed, for example, on how to control costs, usually the thorniest issue, she replied: “It depends on what kind of system you’re devising. And that’s still not at all clear to me, what the body politic will bear.”

Mrs. Clinton’s supporters say voters have forgotten the gory details of the last Clinton health plan, which proposed huge new bureaucracies and new mandates on employers, and assumed that one-seventh of the American economy could be reinvented over the objections of powerful groups like the insurance and pharmaceutical industries.

Rather, her allies say, voters remember her for having tried to change the system.

Mrs. Clinton is quick to admit errors and thereby distance herself from the old plan. “I think that both the process and the plan were flawed,” she said in the interview. “We were trying to do something that was very hard to do, and we made a lot of mistakes.”

But some analysts say the old vulnerability — the memory of what conservatives scornfully called “Hillarycare” — remains, and could be revived in the heat of a presidential campaign. Moreover, the history puts Mrs. Clinton in a peculiar box.

“On the Democratic side, people will hunger for a major proposal,” said Robert J. Blendon, a Harvard professor and expert on public opinion and health. “But she’s extremely vulnerable to Republicans saying, the minute she articulates something, ‘Here we go again, a major expansion of government plans and plans that hurt business.’ ”

The woman who was sharply criticized a decade ago for a lack of political realism is now steeped in it. If her cardinal sin in 1993-94 was overestimating the public’s appetite for change, as many analysts contend, she seems intent on not repeating the error. When employers complain to her about the need for federal action on health care, she said, “I say back to them, ‘Fine, what are you going to do to help us create the consensus that has to develop in order to move the political system?’ ”

In her own search for consensus, Mrs. Clinton hired as her domestic policy adviser Laurie Rubiner, a health policy expert who for many years worked for Senator John H. Chafee, the moderate Rhode Island Republican, until his death in 1999. That has fueled suspicions on the left that Mrs. Clinton is growing too cautious and moving to the center on health care.

She encounters that perception on many issues these days; on health care it has been reinforced by her work alongside prominent Republicans like Newt Gingrich and Senator Bill Frist on goals like upgrading medical information technology.

Still, that cautious and occasionally bipartisan approach could help lighten the ideological baggage of 1993-94, when she ended up in a ferocious battle with small businesses, the insurance industry and the drug companies.

Mrs. Clinton often frames the problem today as one of economics as much as social justice. She asserts that soaring health costs are weighing down American corporations and hindering their ability to compete in a global marketplace, against countries with government-financed health benefits or no expectation of health coverage at all.

In a speech at the Economic Club of Chicago in April, the first of several policy addresses she is giving this year, Mrs. Clinton cited the domestic auto industry. “Profits are up, but so are the costs of health care and energy, adding more than $1,000 to the cost of every car built by the Big Three and driving up family health insurance premiums five times faster than incomes,” she told a group of business leaders.

In a March speech to the American Medical Association, her first appearance before the group since the battles of 1993-94, Mrs. Clinton struck a decidedly pragmatic tone.

“No quick fixes. No Band-Aids,” she told the group. “No partisanship or ideology. Let’s retire the old debates. They haven’t served our country well.”

Mrs. Clinton talked about health care during her 2000 campaign, running an ad that hailed her perseverance in the face of defeat. The problems of cost and coverage have persisted, giving her even more ammunition — and a clear sense of vindication — as she returns to the subject.

There are now, in the most recent estimates, about 45.8 million uninsured Americans (8.3 million of them children), up from 39.8 million in 1994. Premiums for family coverage in employer-sponsored insurance — the way most Americans under 65 get their coverage — have risen by 73 percent in the past five years, according to the Henry J. Kaiser Family Foundation.

On policy and political grounds, Democrats view the return of the health care debate as inevitable in the midterm and presidential campaigns. For the moment, Mrs. Clinton says, Democrats need to fight to protect the existing government health programs.

“If we could get back into control of one or both houses of Congress,” she said, “we could stop the assault on the pieces of the health care system that have provided coverage for people over the last several decades: Medicare, Medicaid, Schip, the Veterans Administration. All of these, because of the budget deficit and the ideology of the Republican majority in the House, are under attack.”

Mrs. Clinton is also looking ahead to what may be the next major legislative struggle in health care: the review and renewal, in 2007, of the State Children’s Health Insurance Program. Mrs. Clinton says it should be “funded to the most we can get.”

She added: “I think you should cover all children who don’t have other access to coverage. We shouldn’t have any uninsured children. But we have to take that step by step.”

Mrs. Clinton said she was also closely watching the bipartisan health plan recently approved in Massachusetts. “If you’ve got an executive and a legislature who are willing to work together,” she said, “you can actually make progress.”

In a sense, though, the heart of Mrs. Clinton’s message seems to be that she is back in the debate. “It’s one of my passions, it’s what I care deeply about,” she said. “It would not be possible for me not to talk about it and try to help change it.”