Although Congress is officially still in recession, key lawmakers are actively involved in intense negotiations to merge the two different bills that, while similar, have some important differences between them.
Experts say Congress is likely to pass the health care bill, but the political ramifications remain to be seen.
"I think that, still, the sense is, if this fails, it would be worse for them politically than if it passes, and I think that's a calculation across the Democratic party," Democratic strategist James Carville said on "Good Morning America" today. "My sense is it's still going to pass it at some point."
Republicans say the health care bill -- and the lack of bipartisanship involved -- could kill support from independents, a key voter group in the last presidential election.
"The problems with the health care bill that used to exist only on the right are now affecting the thoughts of the independent voters," Republican strategist Nicole Wallace said on "GMA." "We have to wait and watch and see. ... I think it will probably pass but I think they will do something that's even uglier than limping across the finish line."
With Democrats facing a brutal congressional election this year and the possibility of losing seats to the GOP, the Democratic leadership is eager to finish and pass the health care bill. But as final negotiations begin, there are several thorny issues that threaten to derail the bill:
'The Cornhusker Kick-back'
California Gov. Arnold Schwarzenegger is the latest in the long line of Republicans to assail the special deal Sen. Ben Nelson, D-Neb., received for his support of the Senate health care bill. Under the deal crafted behind closed doors, Nelson's home state would be exempt from $100 million in Medicaid payments that have been imposed to pay for the costly bill.
"While I enthusiastically support health care reform, it is not reform to push more costs onto states that are already struggling while other states get sweetheart deals," Schwarzenegger said in his annual "State of the State" Wednesday, adding that California's congressional leadership should "either vote against this bill that is a disaster for California or get in there and fight for the same sweetheart deal Senator Nelson of Nebraska got for the Cornhusker State. He got the corn; we got the husk."
While Republicans generally have lambasted the deal, Schwarzenegger's criticism is a new blow because the California governor was one of only a handful of Republicans to support Obama's health care overhaul efforts. The president in October even hailed the governor's backing.
Even Democrats, especially in the House, are angry with the deal. Some insist it should be removed, but they need Nelson's vote to ensure the passage of the bill, an issue that could be tricky to resolve.
The issue of whether the health care bill should include more stringent language on banning federal funding for abortion has become a rocky point for many Democrats.
The House narrowly passed its version only after including tough restrictions demanded by anti-abortion rights Democrats, such as Rep. Bart Stupak of Michigan, but the Senate's version didn't include that language.
Stupak and some other Democrats have been firm about their abortion language but say they are open to working with Senators to craft a compromise.
Another thorny issue is whether the health care bill should include the option of a government-run insurance plan that would compete with private insurers. In August, 60 Democrats signed a bill saying they would only vote for a bill if it included a public option, but much to the chagrin of some, the Senate ended up taking it out to appease lawmakers such as Nelson and Independent Sen. Joe Lieberman of Connecticut.
The Massachusetts Senate Seat
Lawmakers are also closely watching the results of the Massachusetts senate seat formerly occupied by late Sen. Ted Kennedy. On Jan. 19, there is a special election to fill the seat, and if Republican candidate Scott Brown prevails, Democrats would no longer have the 60 votes they need to pass the bill in the Senate, making the final passage even tougher.
Despite these issues, Democrats are confident they can come together on the health care bill, but the negotiations between the two chambers of Congress will be tough with little or no room for error.
On Wednesday, Speaker of the House Nancy Pelosi, D-Calif., was at a loss for words when asked if a final bill would pass by the end of January.
"It's possible, it's possible," Pelosi said as she and chairs of key House committees emerged from a two-hour meeting with President Obama at the White House. "We will bring the bill to the floor when we are ready, and hopefully that will be soon."
Democratic leaders are confident that they will ultimately prevail.
Pelosi said that it has been a "very intense couple of days" as House, Senate and White House staffers engage with each other to review and suggest changes to the language of the legislation.
"I think we are very close to reconciliation respectful of the challenges, policy and otherwise in the House and Senate," Pelosi said, but she wouldn't reveal the details of their meeting with Obama, except to say the work done was "very productive."
The White House said one of the issues the president discussed with lawmakers was how to pay for health care overhaul. As for the question of whether he pushed them to take the fast track approach, White House Press Secretary Robert Gibbs would only say, "The president wants to get a bill to his desk as quickly as possible."
ABC News' Jonathan Karl and Sunlen Miller contributed to this report.