WASHINGTON — The House of Representatives approved late Saturday night a historic bill to remake the U.S. health-care system, delivering President Barack Obama a key procedural victory on his top domestic priority after a lengthy and sometimes emotional day of debate on the nearly 2,000-page measure.

By a vote of 220-215, lawmakers approved a 10-year, $1.055 trillion bill that aims to put in place near-universal health-care coverage in the United States, would require individuals to buy and most businesses to offer coverage, and expand Medicaid. Poorer Americans would get subsidies to buy insurance under the bill, and insurers would be barred from denying coverage to people with pre-existing conditions.

The bill would also establish a government-run health-insurance plan option to compete with private insurers — the controversial "public option" strongly backed by Obama but sharply opposed by Republicans.

Just one Republican, Rep. Joseph Cao of Louisiana, voted for the White House-backed bill. A substitute bill offered by the GOP failed on a vote of 176-258. The House Democrats' bill will now need to be melded with a bill awaiting action in the Senate.

A triumphant Speaker Nancy Pelosi likened the legislation to the passage of Social Security in 1935 and Medicare 30 years later. Before the vote, Pelosi said it was "a historic moment for our nation and for America's families."

House lawmakers began debating late Saturday morning and were immediately caught up in partisan fighting. But House Democratic leaders were upbeat about the bill's prospects after an early afternoon meeting with Obama, who made a rare Saturday trip to Capitol Hill to press members to pass the measure.

Obama made health-care reform a plank of his history-making presidential campaign and this year made a full-court press for an overhaul, lobbying members of Congress and stumping for reform in speeches around the country.

"This bill is change that the American people urgently need," Obama said in the White House Rose Garden after meeting lawmakers Saturday. "Now's the time to finish the job," he said, stressing that the bill is fully paid for and will lower health-care costs for families and businesses.

Action on health reform now moves to the Senate, where Majority Leader Harry Reid, D-Nev., is working to unite his members in time to hold a Senate vote before Christmas, a critical deadline if Democrats are to send health care legislation to Obama's desk by the end of January. The Senate bill would let states opt out of the government-run "public option," but the overall Senate and House measures share broadly similar language.

With the unemployment rate continuing to rise and polls showing the public increasingly jittery about Obama's health care campaign, Democrats are racing to push through an overhaul before what many see as a historic opportunity slips away.

House Democrats needed 218 votes for the bill to pass. Party leaders spent the week trying to shore up support from wavering members of the rank and file who were concerned about abortion and immigration language in the bill.

Members passed an amendment Saturday night that would bar federal funds for abortions. The vote was 240-194.

Thirty-nine Democrats voted against the health-care overhaul bill.

In spirited debate, Republicans charged that the Democrats' bill was an unprecedented expansion of government.

"Speaker Pelosi's takeover of health care spells disaster for patients and doctors," said Rep. Tom Price, R-Ga., a physician. House Republican Leader John Boehner of Ohio said the bill would actually raise the cost of health insurance, as well as produce a "mega-bureaucracy."

House Democratic leaders say that their bill would extend coverage to 36 million Americans. It would set up health-insurance "exchanges" where consumers could shop for coverage, and expand Medicaid beginning in 2013 to people with incomes up to 150 percent of the federal poverty line. Illegal immigrants wouldn't be covered under the bill.

Obama and other Democrats say the "public option" will keep private insurers honest and expand choice. Republicans charge it could lead to private insurers' being pushed out of the market. A trade group representing insurers, America's Health Insurance Plans, e-mailed a round-up of newspaper articles to reporters on Saturday that said the current health-care bills didn't do enough to control rising health-care costs.

Business groups, meanwhile, are bitterly opposed to the requirement on employers to provide their workers with health-care coverage. The requirement applies to all companies but those with annual payrolls under $500,000.

But the AARP and the American Medical Association — the powerful seniors' and doctors' groups, respectively — said last week that they supported the bill.

Obama wants to sign a bill by the end of the year, but legislative action in the Senate could slip until early 2010 — pushing the health-care debate into an election year.

The House Republicans' bill would have allowed Americans to buy insurance across state lines, permitted small businesses to pool together and offer health care at lower prices, ended "junk" lawsuits and taken other steps.

The Democrats' bill would be financed by about $500 billion in cuts to Medicare and Medicaid, as well as new taxes on high-income earners. Employers and individuals who don't buy coverage would also be required to pay fines.

Paying for the legislation is a key difference between the House and Senate measures. Whereas the House bill would tax families making more than $1 million a year, the Senate's would tax insurers offering high-value plans.

The House's bill would also end a longtime exemption for the insurance industry from antitrust laws covering price-fixing and other things. An amendment with similar goals is expected to be offered on the Senate floor when lawmakers debate their version of the reform bill.