The Republican lawsuit targets reinsurance that helps insurance companies provide universal coverage without accounting for pre-existing conditions.
With more than 1 million of the nation's long-term jobless facing a cutoff of federal unemployment benefits on Saturday, a bipartisan pair of senators have called for an early January vote on a three- month extension of the benefits.
But even if the measure proposed by Sens. Jack Reed, D-R.I., and Dean Heller, R-Nev., passes the Democratic-controlled Senate, its prospects are not clear in the Republican-run House, where many in the majority say the extension is unnecessary or too costly.
Reed pushed back at GOP accusations that the benefits give the long-term jobless little incentive to find work, saying, "This is not a program that people are leaving good jobs or not looking for jobs because they're doing very well."
"This is just enough to keep people going -- in some cases, barely enough to keep people going," he said Thursday. "From a human level, cutting, certainly, 1.3 million Americans off this lifeline - - and there will be more in the [coming] months -- doesn't make any sense, and it's not something that we should be doing."
Without legislation, benefits for 1.3 million workers unemployed for longer than 26 weeks will expire Saturday. An additional 1.9 million of the nation's jobless are predicted to experience the same fate in the first half of 2014.
The cost of extending the program is about $25 billion for one year.
Senate Majority Leader Harry Reid, D-Nev., hasn't said if he will call a procedural vote on the proposed benefits extension by Jan. 6, as Reed and Heller want. But Reid has said extending long-term unemployment benefits will be a priority when senators return to Washington after their holiday break.
Democratic lawmakers have jumped on Republicans for their reluctance to extend the benefits, with House Minority Leader Nancy Pelosi, D-Calif., calling the GOP's position "immoral."
It's "an abdication of our obligation to do what we can to support those who worked hard, played by the rules and lost their jobs through no fault of their own," she said.
Sen. Bernie Sanders, I-Vt., told MSNBC that the benefits will help strengthen the economy by giving the long-term unemployed money to spend on goods and services.
He added that public pressure on Republicans is critical if an extension of benefits is to pass Congress, something he said helped end the 16-day partial government shutdown in October.
"The American people [told Republicans in October] you can't shut down the government because you're unhappy about something," Sanders said. "So when the American people get involved and speak out, we are going to win this fight, and I believe that is what is going to happen."
Republican leaders mostly have been quiet about the debate in recent days. But during the bipartisan budget negotiations this month, Republicans complained that Democrats at the last minute pushed for an extension of the unemployment benefits without offering a way to pay for them.
Such a scenario, House Budget Committee Chairman Paul Ryan, R- Wis., recently told Fox News, "would have blown a hole in our deficits."
Ryan added that unlike in 2008, when President George W. Bush proposed the initial extension of unemployment insurance as the economy was reeling from the Wall Street meltdown, "we have a lot of evidence showing that it [now would] prolong unemployment."
Republicans also have balked at extending the benefits on the grounds that the unemployment rate has steadily fallen his year.
"When you allow people to be on unemployment insurance for 99 weeks, you're causing them to become part of this perpetual unemployed group in our -- in our economy," Sen. Rand Paul, R-Ky., told Fox News.