For their part, Democrats and President Barack Obama said they would work to win over skeptics, saying the bill has immediate benefits and addresses the nation's shaky fiscal condition, The New York Times reported Monday.
Besides making healthcare votes fodder on the election trail, Republicans vowed to challenge the legislation's constitutionality and work with state governments interested in blocking its implementation, the Times said.
"We ought to focus on not the political stakes, but the stakes for the country," David Plouffe, an adviser to Mr. Obama, said on ABC's "This Week." "We're going to go out there and not just talk about what we're for, but what the Republicans are voting against."
Meanwhile, attorneys general in three states -- Virginia, Florida and South Carolina -- indicated they will challenge the measure, saying it violates the Constitution by requiring individuals to purchase insurance. In an interview Sunday, Virginia Attorney General Ken Cuccinelli said his challenge raises two arguments -- one, the federal bill conflicts with a state law saying no Virginian may be compelled to buy insurance and two, Congress does not have authority to impose the mandate under its powers to regulate interstate commerce, the Times said.
The White House and Democrats were readying legal arguments and coordinating a state-by-state response to possible challenges, aides said.
The point-counterpoint isn't limited to elected officials. Thomas J. Donahue, president of the U.S. Chamber of Congress, vowed to oppose the measure "through all available avenues -- regulatory, legislative, legal and political," the Times wrote. Organizations supporting the legislation, including AARP and labor unions, said they would defend the bill through advertising that highlights what they see as benefits.