The nonpartisan Congressional Budget Office estimated overturning the reform signed by Obama last year would add about $230 billion to the deficit by 2021 and result in 32 million fewer people having health insurance.
That was a blow to Republican promises to cut the federal budget deficit.
Democrats, who still control the Senate despite losses at last year's congressional elections, promised they would protect the healthcare reform, Obama's signature legislative victory.
"I don't think they expect, certainly they shouldn't expect, the Senate to go along with this kind of wholesale repeal," assistant Senate Democratic leader Dick Durbin told reporters.
The law is designed to rein in medical costs, cover millions of uninsured people and reform insurance practices, including requiring coverage for patients with pre-existing conditions and other consumer protections.
The Republican-controlled House of Representatives will vote on repealing the law next week in what will probably be a symbolic gesture given the Senate's likely opposition.
In a preliminary estimate, the CBO said repealing the healthcare overhaul would increase the federal budget deficit by roughly $145 billion by 2019. That figure would rise to about $230 billion by 2021, the CBO said.
New House Speaker John Boehner, who has promised to bring down the $1.3 trillion federal deficit, disputed the numbers.
"CBO is entitled to their opinion," Boehner told reporters. "When you look at it dollar by dollar, you can tell that the numbers just don't add up."
Debate on repeal of the healthcare law, another core Republican promise during the 2010 campaign, is scheduled to begin in the Republican-controlled House on Friday with a vote planned for next week.
Public opinion split
Polls show public opinion on the law is split. Republicans won control of the House last year after promising to repeal it.
They argue the law places job-killing burdens on business and is unconstitutional because it requires individuals to purchase health insurance if they are not already covered.
Democrats pounced on the report by the CBO, which analyzes legislation for its impact on government spending and revenues and develops forecasts of U.S. economic performance.
Representative George Miller said it showed the Republicans' "budget-busting repeal bill will kill jobs, raise costs, and deny critical care to Americans who need it."
A House committee began meeting on Thursday to put together rules governing the House floor debate of the healthcare law. That panel is expected to refuse to let Democrats offer amendments on the bill that could pass as soon as Jan. 12.
Another key battle over healthcare reform could come by March when a temporary funding measure for the government runs out. Republicans balked at $1 billion to start implementing the healthcare law as part of a bigger appropriations bill that Democrats tried and failed to move last year.
Lawmakers instead opted for a stop-gap measure that keeps funding mostly at current levels through March 4.
By John Whitesides and Richard Cowan
Last Updated: 2011-01-06 16:56:21 -0400 (Reuters Health)
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