Democratic presidential candidate John Kerry is tying together two of the country’s biggest problems – job losses and rising health care costs – and blaming President Bush for both.

Kerry was promoting his plans to counter health costs Thursday in a speech to the International Association of Fire Fighters convention in Boston and during one of his “front-porch visits” at a home in Derry, N.H.

His campaign commissioned a study that says high health care costs are a key reason for the weak job market. Businesses that pay more for health insurance have to pay more for workers, which leads to cuts in employment, the study says.

Kerry blames Bush, saying the president hasn’t done anything to reduce health costs.

“America can’t afford four more years of a plan that hasn’t saved us a single dime or created a single job,” he said in a statement late Wednesday. “We need a president who understands that our businesses can’t thrive when they are saddled with soaring health care costs and neither can our economy.”

Bush’s campaign says the president has a plan to cut health care costs, which are rising at $60 billion to $100 billion annually, according to the administration. But the campaign says Kerry and running mate John Edwards, both senators, are among those standing in the way. Bush favors caps on medical malpractice claims.

“All across the country, doctors are being litigated out of practice and American families are finding it more difficult to find health insurance because senators like Kerry and Edwards are opposed to commonsense fixes,” said Bush campaign spokesman Steve Schmidt.

Bush would like to cap non-economic damages, including pain and suffering, to $250,000, among other measures. Kerry and Edwards, a former trial attorney who made millions winning medical malpractice cases, oppose Bush’s limit.

The Democratic ticket supports another kind of tort reform, including requiring that a qualified specialist certify the merits of a medical malpractice lawsuit before it can proceed.

New Hampshire has one of the nation’s lowest unemployment rates and highest rates of health insurance coverage.

The state is a small stake in the electoral college, with just four of the 270 electoral votes needed to win the Nov. 2 election. But it could have made the difference for Democrat Al Gore in 2000, and is being contested by both candidates this year. Bush won the state over Gore by 1 percentage point.

Bush has visited New Hampshire seven times as president. Kerry traveled there extensively while campaigning for its Democratic presidential primary last January.

Kerry also says he would lower health care costs by having the federal government pick up three-fourths of an employer’s costs for catastrophic care, which he says would result in about a 10 percent drop in premiums.

He would give tax credits for health care to small businesses, people aged 55 to 64 and low- to middle-income workers, and allow the federal government to negotiate better drug prices through Medicare and import drugs. He also says he would eliminate waste, fraud and abuse in the medical system through technology.

Bush also favors allowing small businesses to pool their resources so they can offer low premiums.