In one of the most animated speeches of two days of debate, Rep. George Miller, D-Calif., said repeal would return power to insurance companies. "Has anybody, any family in America, any single mother, any spouse, any child, any grandparent met a more bureaucratic system than the American health insurance system? There is no more bureaucratic system."
Senate Majority Leader Harry Reid has said the legislation will not see the light of day there, but the GOP leader, Sen. Mitch McConnell of Kentucky, said bluntly, "I assure you we will" have a vote on it.
The law faces another challenge, well beyond the reach of Obama's veto pen. More than half the states have filed suits against it, and while some judges have upheld the legislation, one recently ruled it was unconstitutional to require individuals to purchase insurance. The Supreme Court is widely expected to have the final word.
The Obama administration has made a major effort in recent days to emphasize parts of the bill that have met with public approval, including one that permits children to age 26 to remain on their parents' policies if they do not have on-the-job coverage of their own. Democrats also argue that repeal would short-circuit other changes yet to take effect, including a ban on the insurance industry's practice of denying coverage or charging sharply higher premiums on the basis of a pre-existing medical condition.
Republicans intend to address the same issues with legislation they say they will bring to the House floor in the coming months, according to officials who have been involved in discussions on the issue, but no details were immediately available.
Last year, for example, the Republicans proposed a 10-year, $25 billion program to help states fund programs in which high-risk individuals could receive affordable coverage.
GOP leaders are working on the assumption that the repeal legislation will not become law, and they intend to draft future bills as changes to the structure that Obama and Democrats put into place.
On one point, they conceded no change was warranted. Majority Leader Eric Cantor, R-Va., told reporters on Tuesday seniors would be permitted to keep the $250 they have been promised to help defray the cost of drugs under the Medicare prescription benefit.
The legislation Obama signed last year was sweeping in its scope.
The Congressional Budget Office said at the time that when fully enacted, it would spread coverage to tens of millions who now lack it and - in a forecast rejected by Republicans - reduce federal deficits over the next decade.
Beginning in 2014, millions of Americans would be required to carry health insurance, whether through an employer, a government program, or their own purchase. New insurance marketplaces called exchanges would open in each state, enabling individuals and small businesses to pick from menus of private plans that met government standards. Federal subsidies would help defray the costs.