The four days that Sen. John F. Kerry (D-Mass.) is devoting to speeches about health care are part of a broad effort this week by both parties to affirm their commitment to a priority among voters, even as domestic concerns have been overshadowed lately by developments in Iraq.

As the presumed Democratic presidential nominee continued yesterday to promote his plan to constrain health costs and extend coverage to 27 million uninsured Americans, Republicans and Democrats in Congress are laying out repackaged versions of their health care proposals. Meanwhile, President Bush's top health adviser declared Monday that the administration has pursued "an aggressive set of reforms" to make health care more affordable.

Such jockeying is timed partly to coincide with the second annual "Cover the Uninsured Week," sponsored by an eclectic coalition that largely agrees on the problem, if not how to solve it.

The House yesterday approved two Republican-backed bills designed to make health care more affordable. One would limit damage payments in medical malpractice lawsuits. The other would let people roll over from one year to the next $500 in pretax funds in flexible savings accounts used to pay for health costs, such as co-payments, not covered by insurance. A third GOP bill, aimed at creating insurance purchasing pools for small businesses, was expected to be passed today.

In a deeper sense, this week's surge of attention to health care reflects the issue's place in the political landscape. The cost and accessibility of the U.S. health care system rank as a substantial concern among voters, with three-quarters of Americans saying that expanding health insurance is a very important priority for the president and Congress to address, according to surveys by the Kaiser Family Foundation.

More importantly, health care is a main issue in which voters say they trust Democrats more by a wide margin to deal with the problem. A recent Kaiser survey found 32 percent of respondents said they believed the Democratic Party would do a better job handling the issue, compared with 16 percent who favored the GOP.

Kerry is trying to capitalize on that perception, while the GOP is trying to blunt that advantage. The Democratic candidate "is trying to make health care a major issue" in the November elections," said Robert Laszewski, a nonpartisan analyst here who follows the politics of health care. "He doesn't have the national security advantage, the war on Iraq advantage, but he's got the health care advantage."

Compared with the GOP health care agenda in the White House and on Capitol Hill, Kerry's plan is far more expensive and would help far more people. According to Kenneth E. Thorpe, an Emory University professor who has analyzed both candidates' health platforms, Kerry's would cost $176 billion by 2010 and allow 26.7 million people to gain coverage during the next four years. Bush's proposals would cost $27 billion and extend coverage to 2.4 million people.

Bush's proposals, mirroring GOP ideas circulating on Capitol Hill, mainly rely on tax breaks to help people purchase insurance policies, relaxation of state insurance rules to allow small businesses to band together to buy insurance at lower rates, and tax-preferred savings accounts for medical expenses that were part of the Medicare law Congress enacted last year.

Yesterday, during an appearance in Orlando, Kerry touted his more ambitious agenda and said that Bush did not do all that he promised to make prescription drugs more affordable for seniors.

Ron Pollack, executive director of Families USA, a consumer health lobby that is an organizer of Cover the Uninsured Week, echoed the belief that major health legislation is unlikely to pass Congress this year, and that it remains unclear what kind of consensus may emerge. Still, Pollack said: "I think the most important thing is, people from both political parties feel this is a salient enough issue that they need to have a plan."