Washington (CNN) -- President Obama is set to claim final victory on his top domestic priority Tuesday by signing into law a package of changes to the newly enacted health care reform bill.
The signing ceremony at a community college in northern Virginia will culminate almost a year of fiercely partisan debate and a tortuous legislative journey on the proposals generated by Democrats and unanimously opposed by Republicans.
Due to a shifting political landscape, Democrats eventually needed the separate bill being signed Tuesday to make changes in the original legislation in order to get the overall package passed by Congress.
Among other things, the "fixes" bill significantly expands health insurance subsidies for lower- and middle-income families while watering down a tax on expensive health policies.
The bill also increases the overall cost of the health care reform legislation to $940 billion over the next 10 years, $65 billion more than the original health care bill Obama signed into law last week.
In addition, it overhauls the national college student loan system by shifting government funding for loans away from commercial banks to new education initiatives. Until now, commercial banks have received federal subsidies to provide student loans.
The "fixes" bill received final legislative approval last Thursday in a 220-207 vote in the House of Representatives. No Republicans backed the measure, which GOP leaders insist will lead to cuts in critical Medicare services while doing little to slow spiraling medical costs.
Earlier in the day, the Senate approved the plan on a 56-43 vote, also without any Republican support.
The congressional wrangling, which included late night votes and acerbic floor debate, reflected the political split throughout the country over health care reform. Polls show the American public remains sharply divided, and conservative activists cheered on by Republicans continue to hold rallies against the legislation.
Senate Minority Leader Mitch McConnell, R-Kentucky, recently told CNN that Republicans would use the slogan "repeal and replace" with regard to the health care legislation in their congressional campaigns later this year.
While a repeal of the legislation is considered unlikely, House Speaker Nancy Pelosi, D-California, questioned the strategy by her opponents, noting it would require GOP candidates to favor ending popular benefits in the legislation, such as preventing insurance companies from denying coverage because of pre-existing conditions.
"They want to reverse and repeal a prohibition on denying care on the basis of a pre-existing condition," Pelosi said Monday. "Can you imagine making that case?"
Democrats argue the health care reform plan, estimated to extend coverage to 32 million Americans, will reduce federal budget deficits while giving consumers greater leverage with private insurance companies.
"It's about protecting the middle class so that they can continue to afford the insurance they may like," or purchase desired coverage at a lower cost because of increased competition, Pelosi said.
Throughout the congressional debate, Republicans used every parliamentary tool available to try to block both the overall health care bill and the "fixes" measure.
Last week, they forced the Senate to begin deliberations on a series of proposed amendments and motions on the "fixes" bill. All were defeated, but they were intended to force Democrats to cast unpopular votes in the run-up to November's midterm elections.
Initially, it appeared that Congress would pass a compromise health care bill when the House and Senate approved their own versions last year. However, the political landscape shifted in February when Republican Scott Brown won a special election in Massachusetts to fill the Senate seat formerly held by Democrat Edward Kennedy, the longtime champion of health care reform who died last year.
Brown's victory cost Senate Democrats the 60-seat majority they needed to overcome a Republican filibuster against a compromise health care bill. In response, Democrats devised a two-bill process in which the House passed the Senate version unchanged, making it law when signed last week by Obama. And then it also passed the accompanying "fixes" bill to change provisions in the Senate legislation that some House members found unpalatable.
The "fixes" bill was then proposed under reconciliation rules in the Senate that apply to bills involving the budget. Such bills need only a simple majority of 51 votes to pass.
Specific provisions in the "fixes" bill include:
-- Closing the Medicare prescription drug "doughnut hole" by 2020. Under current law, Medicare stops covering drug costs after a plan and beneficiary have spent more than $2,830 on prescription drugs. It starts paying again after an individual's out-of-pocket expenses exceed $4,550. Senior citizens stuck in the doughnut hole this year will receive a $250 rebate.
-- Raising the threshold for imposing the "Cadillac" tax on expensive health insurance plans to coverage valued at more than $10,200 for individuals and $27,500 for families. The tax won't kick in until 2018.
-- Imposing an additional 3.8 percent Medicare payroll tax on investment income for individuals making more than $200,000 a year and couples making more than $250,000 a year.
-- Eliminating a special exemption for Nebraska, known as the "Cornhusker Kickback," from all new Medicaid expenses. The federal government will instead assist every state by picking up 100 percent of the costs of expanded Medicaid coverage between 2014 and 2016, and 90 percent starting in 2020.
-- Reducing the fine for individuals who fail to purchase coverage from $750 to $695.
-- Increasing the fine on large companies failing to provide health coverage for workers from $750 to $2,000 per employee.
CNN's Alan Silverleib and Tom Cohen contributed to this story.