The U.S. Senate passed the $871 billion overhaul of America's health care system after 24 consecutive days of often-bitter debate and deep partisanship, but even as senators and President Obama hailed this as a historic vote, they will face major obstacles when they return to their desks in January.
Republicans today vowed to continue fighting the health care bill, which passed in the Senate early this morning on a 60-39 party-line vote, and Democratic leaders will have to resolve the differences between the House and Senate bills.
"This fight isn't over. My colleagues and I will work to stop this bill from becoming law," Senate Minority Leader Mitch McConnell, R-Ky. said before the vote today.
Sen. Orrin Hatch, R-Utah, agreed, and said health care should not have become such a partisan issue.
"Frankly, this is just step one," Hatch said in an interview today with MSNBC. "It's not passed yet, and it's got a long way to go."
Before leaving for his vacation in Hawaii, Obama praised the Senate bill despite the fact that not a single Republican voted in favor of it. Obama had repeatedly pushed for bipartisanship and held several private meetings with Republican lawmakers to discuss health care.
"This will be the most important piece of social legislation since the Social Security Act passed in the 1930's and the most important reform of our health care system since Medicare passed in the 1960's," the president said.
He called health-care legislation the "largest deficit-reduction plan in over a decade," and said he looks forward to working with both chambers of Congress "over the coming weeks" to bring a final bill to his desk. The president is likely to face rising criticism from the GOP in January; Republicans say they want to see more action on the economy and jobs front.
All 58 Democrats and two independents voted for the health care bill, as expected, without any Republican support. Sen. Jim Bunning of Kentucky, who is retiring at the end of his term, was the lone Republican who did not vote.
In a celebratory press conference, jubilant Democratic leaders invoked the memory of the late Sen. Ted Kennedy, whose wife Vicki watched the vote from the Senate gallery.
"This is a victory for the American people," Majority Leader Harry Reid, D-Nev., said. "This morning's vote brings us one step closer to making Ted Kennedy's dream a reality."
Others hailed the historic nature of the health care vote.
"This is probably the most important vote that every sitting member of the Senate will cast in their tenure here," Sen. Chris Dodd, D-Conn., told reporters.
The Senate's health care vote today marks the first roll call on Christmas Eve in more than a century, Congressional Quarterly reported, citing the Senate historian. The last such vote came in 1895 to overturn a law that banned former Confederate Army officers from employment in the U.S. Army.
After this morning's vote there were cautious congratulations from medical groups. The president of the American Medical Association, which officially endorsed the bill, dubbed today's Senate action a "historic vote" but warned that there is much more work ahead.
"The AMA supported passage of the bill because it contains a number of key improvements for our health care system, which currently is not working for far too many patients or the physicians who dedicate their lives to patient care," the organization's president, J. James Rohack, said in a written statement. "While this vote closes one chapter of the legislative process, the hard work is not yet done."
Some medical experts argue that in the process to implement better health care for Americans, politics became more important than concern for people's well-being.
"Politics has caused compromises that may make the 'victory' hollow in that $1 trillion will not buy adequate, truly affordable health care for a large segment of the population," said Arthur Garson, dean of the School of Medicine at the University of Virginia.
Republicans tried every maneuver they could to defeat or delay the health care bill, at one point even forcing clerks to spend a day reading hundreds of pages out loud. Today, they continued their attacks.
"The Democrats have put a $2.5 trillion lump of coal in the stocking of every American knowing that their risky health care experiment still increases premiums, still cuts Medicare, and still enacts hundreds of billions of new taxes to pay for it," Republican National Committee Chairman Michael Steele said in a written statement. "Scrooge would be proud."
Sen. James Inhofe, R-Okla., who left town and missed every vote on the health care bill, returned to the Senate today to cast his "no" vote.
Democratic senators worked through weekends behind closed doors to cobble together the 60 votes needed to defeat a series of Republican motions to block the bill. At the end, they came together, but after giving many concessions to Democratic senators, such as Ben Nelson of Nebraska, who had expressed reservations about some components of the health care bill, in a move that Sen. John McCain, R-Ariz., dubbed "one of the great Bernie Madoff gimmicks."
Health Care Overhaul: What Does it Mean?
The Senate health care bill would cost $871 billion over the next 10 years and expand access for 31 million Americans who don't have health insurance. It counts on lower Medicare costs, taxes on the insurance industry and medical device makers, as well as a special tax on high-cost insurance plans, to pay for the legislation.
Every person would be required by the government to have insurance or pay a fine. Medicaid would be greatly expanded for the poor, and people making up to $88,000 for a family of four would get help from the government to pay for insurance.
Health industry experts had mixed views of the Democrats' health care overhaul efforts. Some said it will hurt rather than help.
"The U.S. is dramatically centralizing federal control over the funding and also important aspects of the delivery of health care in the United States -- as has been happening recently in Norway, Ireland, Italy and other parts of Europe," said Richard Saltman, an international health expert at Emory University.
But others said it's a substantial step toward reform.
"It's a start," said Donald Kemper, chairman and chief executive of non-profit group Healthwise Incorporated. "It focuses on reducing the inequities and that's not a bad place to start."
Republicans argue that the Senate health care bill would add an extra $1 trillion to the budget deficit even though the nonpartisan Congressional Budget Office has said it would reduce the deficit by $132 billion over 10 years -- a figure often touted by the president.
So what happens now? The Senate legislation will now have to be reconciled with the House bill, which passed in November. A conference committee from both chambers will attempt to merge the two bills, a process which is expected to go into February. The House returns on Jan. 12, the Senate Jan. 19, which leaves little time to get the bill to the president before his State of the Union address. Both chambers have to approve exactly the same bill, with a simple majority, before sending it to the president.
Democratic leaders have expressed confidence that they can clear this final hurdle, but they are likely to face a tough time resolving differences among members of their own caucus. Some liberal members of the House were upset by the Senate's removal of the public option plan to appease senators such as Nelson and independent Sen. Joe Lieberman of Connecticut.
"A conference report is unlikely to sufficiently bridge the gap between these two very different bills," Rep. Louise Slaughter, D-N.Y., chairwoman of the House Rules Committee, wrote in a blistering CNN.com column Wednesday. "It's time that we draw the line on this weak bill and ask the Senate to go back to the drawing board. The American people deserve at least that."
Even though both health care bills were crafted by Democrats and are similar in some ways, there are several significant differences between the two.
Some senators, such as Nelson, have warned that they could yank their support for the health care bill if changes are made. For some members of the Senate, the House version of the health care bill was dead on arrival and many say that members of the House will simply have to cave in.
Meanwhile, some House Democrats, such as Rep. Bart Stupak of Michigan, who wanted strict language prohibiting federal funding for abortion, say they are unhappy with the language in the Senate bill and other concessions given to senators. Stupak called the bill unacceptable but added, "I remain optimistic that we can work this out."
Deputy White House press secretary Bill Burton also expressed optimism, telling reporters today the House and Senate versions were "95 percent similar."
"We're going to be actively working to iron out the rest of the differences and get a bill passed and signed," Burton said.
Here are some key differences between the House and Senate bills:
The Senate bill curbs costs by taxing so-called "Cadillac plans," high-deductible insurance plans that some believe are one of the reasons for high insurance costs. The plan would impose a 40 percent tax on insurance coverage in which premiums are more than $8,500 for an individual and $23,000 for a family.
The plan drew fire from the union groups, many employees of which often negotiate lower salaries in exchange for better health care coverage. Some House Democrats are also opposing it for that reason.
In an interview with NPR Wednesday, Obama said this tax would be a good idea.
"Taxing Cadillac plans that don't make people healthier, but just take money out of their pockets because they're paying more for insurance than they need to -- that's actually a good idea and that helps bend the cost curve," Obama said in an interview with NPR.
The Senate bill targets the wealthy also, but by increasing the Medicare payroll tax on individuals who make $200,000 a year and couples who make more than $250,000.
The House, on the other hand, does not include a tax on "Cadillac plans" but it does impose an income tax on the wealthy. Under the House plan, there would be a tax surcharge of 5.4 percent on income over $500,000 in the case of individuals and $1 million for families.
Abortion is likely to be the key point of contention between Democrats in the Senate and the House when they try to reconcile the different bills.
Democrats in both chambers have been deeply divided over abortion language in the health care legislation. The House bill includes Stupak's amendment, which takes federal funding restrictions for abortion further with new language that cuts access to abortions for people who receive federal subsidies and those who purchase insurance through the health insurance exchange, a marketplace where people would be able to shop for and compare insurance plans. It also bans insurance companies participating in the exchange from offering abortion services.
The Senate includes slightly less restrictive language on abortion. In that version of the health care bill, states have the option of banning coverage in insurance plans brought in insurance marketplaces.
Democratic leaders in the House would be happy to concede to the Senate version -- liberal members of the party were unhappy with the abortion language inserted in the bill -- but Stupak told ABC News last week he will not vote for a bill that does not include his language. There are several anti-abortion Democrats in the House who insist on this as a condition to pass the bill.
"We plan on keeping the amendment we had and we've had good conversations with White House officials," Stupak said. "We haven't reached a common ground."
The Senate plan does not include the option of a government-run insurance plan, a thorny issue among Democrats. The plan initially had a public option in which states would have the choice of whether they wanted to participate. But Democratic leaders did away with that provision to appease lawmakers such as Nelson and Lieberman.
The House health care bill, however, includes a public option in what becomes one of the biggest health care policy differences between the two bills. Under the House's public option plan, the government would negotiate rates with insurance companies instead of setting fees, as it does in Medicare.
At least 50 Democrats in the House are on the record as saying they will not vote for a bill without this option while Nelson and Lieberman have refused to support a bill that does include a public option.
In her column, Rep. Slaughter said by scrapping the public option, "the Senate has ended up with a bill that isn't worthy of its support."
"Although the art of legislating involves compromise, I believe the Senate went off the rails when it agreed with the Obama Administration to water down the reform bill and no longer include the public option," she wrote.
Obama Monday tried to downplay the differences over the public option, saying that debate is not the most important aspect of the bill.
"This is an area that has just become symbolic of a lot of ideological fights. As a practical matter, this is not the most important aspect to this bill -- the House bill or the Senate bill," the president said in an interview with American Urban Radio Networks, adding that "the Senate and the House bills are 95 percent identical."
In an interview with PBS Wednesday, the president reiterated that point, saying he will sign a bill even if it doesn't contain a public option.
"Would I like one of those options to be the public option? Yes. Do I think that it makes sense, as some have argued, that, without the public option, we dump all these other extraordinary reforms and we say to the 30 million people who don't have coverage: 'You know, sorry. We didn't get exactly what we wanted?' I don't think that makes sense," Obama said.
ABC News' Jonathan Karl contributed to this report.