The House Ways and Means Committee on Thursday advanced GOP legislation to repeal and replace ObamaCare on a party line vote, moving the process forward even as the bill faces headwinds. 
 
 Republican leaders are pushing forward with the process on a fast timetable, even as many conservatives strongly object to the bill, known as the American Health Care Act, and centrists harbor their own reservations. 
 
 The committee markup lasted over 16 hours, stretching until after 4 a.m. Thursday before the measure was approved, 23-16. Republicans blamed Democrats for purposely dragging the process out with a range of amendments. The measure now goes to the House Budget Committee, with plans for a vote in the full House within weeks. 
 
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 Democrats said Republicans were wrongly advancing the bill in the middle of the night. The House Energy and Commerce Committee, meanwhile, was still going, working through the night. 
 
 “Here were are at almost 2 o’clock in the morning taking a vote when the American people have gone to sleep,” said Rep. Richard Neal (D-Mass.), the Ways and Means Committee’s top Democrat. 
 
 Democrats were generally more vocal, denouncing a range of measures in the bill, while Republicans voted down amendment after amendment. 
 
 The committee called a markup without a score from the Congressional Budget Office (CBO), meaning lawmakers voted without an analysis of how much the bill will cost or how many people would lose coverage. 
 
 Democrats argued that Republicans wanted to move forward without a score because it would cast a bad light on their healthcare plan. 
 
 "You’re fearful the CBO will provide answers to questions that you don’t like," said Rep. Sandy Levin (D-Mich.). 
 
 House Ways and Means Committee Chairman Kevin Brady Kevin Patrick BradyTrump gets recommendation for steep curbs on imported steel, risking trade war Business groups pressing for repeal of ObamaCare employer mandate Watchdog: IRS issued bonuses to employees with conduct issues MORE (R-Texas) pushed back on Democratic concerns about the markup occurring without a CBO score. 
 
 "We expect CBO to have a thoughtful, thorough, comprehensive score to us before this recommendation goes to the Budget Committee, comes to the House floor," he said. 
 
 Republicans also pushed aside a Democratic amendment aimed at highlighting the "Trump promise" that everyone would have health insurance under a GOP plan. 
 
 The amendment from Rep. Earl Blumenauer Earl BlumenauerSessions' war on marijuana a handout for illegal operators Fox's Wallace: 'It's a mistake' for Dems to boycott State of the Union WHIP LIST: Dems boycotting Trump’s State of the Union MORE (D-Ore.) would have prevented the GOP ObamaCare replacement bill from taking effect until the CBO ensured that the bill would provide health insurance for "all taxpayers and their dependents." 
 
 The amendment was an attempt to draw attention to President Trump's comment in January to The Washington Post that a GOP plan should provide "insurance for everybody." 
 
 Republicans acknowledge that their bill will cover fewer people than ObamaCare but say that it is not trying to compete with the health law, which includes a mandate requiring coverage. 
 
 Republicans sidelined the amendment on parliamentary grounds, saying that it was not germane, as they did with a range of other Democratic amendments. Blumenauer said lawmakers should "give the American people the 'Trump guarantee.'" 
 
 Later, Rep. Lloyd Doggett (D-Texas) held up Trump’s quotation on a poster. 
 
 Republicans blamed Democrats for dragging out the process with off-topic amendments. 
 
 Democrats denounced Republicans for repealing a pair of ObamaCare taxes on high-income people. Levin asked “how this isn’t a boondoggle for the very wealthy while really assaulting the interests of typical middle class families.” 
 
 Rep. Peter Roskam (R-Ill.) defended the repeal of one of the taxes, on investment income. “If investment is good, then why are we raising taxes on investment?” he said. 
 
 Democrats noted that the repeal of the higher Medicare taxes on high earners is projected to reduce the expected solvency of the Medicare trust fund by three years. 
 
 More broadly, Brady praised repealing all of the ObamaCare taxes. “Do you want all these taxes on people, or do you want affordable healthcare?” he said. 
 
 Levin also criticized the new Republican tax credit for failing to give enough help to low-income people, citing a Kaiser Family Foundation study that found the new credit would provide an average of 36 percent less help than the assistance under ObamaCare. 
 
 Democrats offered a range of other amendments, including to prevent enactment of the bill if it was found to raise out of pocket health costs and to allow states to choose to keep ObamaCare, among other issues. 
 
 Doggett unsuccessfully offered a motion to delay the Ways and Means markup until next week, arguing that the bill is a "legislative surprise package" released just two days before the committee vote. 
 
 "If you have nothing to hide, a week will not impair your effort," he said. ||||| Now that Republicans have rolled out their legislative plan to repeal and replace the Affordable Care Act, House Speaker Paul Ryan and other Republican congressional leaders have begun to sell the bill to build the support required for its passage. 
 
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 House of Representatives: 216 
 
 In the House of Representatives, Republicans must amass a simple majority to pass the legislation. While that threshold is typically 218 ayes when all House seats are filled, that number has decreased to 216 because of five vacancies. It could change if there are additional resignations or if any of the vacancies are filled through special elections before a vote. 
 
 The magic number: 21 
 
 Since there are currently 237 Republicans in the House and none of the 193 Democrats are expected to vote in support of the GOP’s plan, Ryan can afford to lose up to 21 of his Republican colleagues before granting concessions to any conservatives whose concerns have inspired them to withhold their support. A 238th Republican could be added if new CIA Director Mike Pompeo's former Kansas district remains in GOP control after its April 11 special election, in which case the magic number would become 22. 
 
 While it currently would take only 21 House Republicans to kill the bill or force leadership into changes and several are already pressing leadership to make additional changes, Ryan predicted the bill will ultimately pass. 
 
 “I have no doubt we’ll pass this, because we're going to keep our promises,” Ryan told reporters on Tuesday, adding that every congressional Republican as well as President Trump “made a promise to the American people and the promise we made to the American people is we're going to repeal and replace Obamacare.” 
 
 Senate: 50 
 
 In the Senate, no Democrats or independents are expected to vote in favor of the GOP’s plan. But Republicans are expected to vote on the plan under a procedural mechanism known as budget reconciliation, which also requires only a simple majority for passage and bars filibustering. Senate Majority Leader Mitch McConnell has the luxury of a Republican White House, where Vice President Mike Pence’s role as president of the Senate affords him the exclusive right to break tie votes in the upper chamber. 
 
 The magic number: 2 
 
 With 52 Senate Republicans, if three or more conservatives vote against the bill, Pence won’t have a chance to cast a tie-breaking vote. 
 
 Already, Sens. Rand Paul and Mike Lee have expressed their strong opposition to the current state of the bill, placing its success in jeopardy. Sens. Susan Collins, R-Maine, and Ted Cruz, R-Texas, also have deep concerns about the legislation. ||||| Story highlights The Prevention and Public Health Fund was created under the Affordable Care Act 
 
 Republican critics say it is a "slush fund" that has been spent on Zumba classes and massage sessions 
 
 Washington (CNN) Public health advocates are warning lawmakers the GOP plan to repeal Obamacare will eliminate nearly $1 billion in Centers for Disease Control and Prevention funding used for programs like preventing disease outbreaks and childhood lead poisoning. 
 
 But Republican critics say the Prevention and Public Health Fund, which amounts to 12% of CDC's budget, is a "slush fund" that has been spent on Zumba classes and massage sessions. Their proposal includes a new fund that they say provides states "broad flexibility" to address local health concerns. 
 
 The Republican bill would eliminate the fund, created under the Affordable Care Act, which has grown from a small slice of the CDC budget to providing $931 million last year. 
 
 It funds heart disease and stroke prevention, immunization, lead poisoning prevention and diabetes prevention, mostly through grants to states and local programs, according to the CDC. 
 
 CDC's website says losing this funding would cripple officials' ability to detect, prevent and respond to health threats including pandemic flu. 
 
 Read More ||||| The array of groups taking strong positions against the bill is evidence that its potential consequences extend far beyond health insurance coverage, to much of the nation’s economy. 
 
 The opposition is also a powerful reminder of how many past efforts to overhaul the American health care system failed because of resistance by major interest groups. Winning the support of the health care and insurance industries allowed the Obama administration in 2010 to push through the most significant health care legislation since President Lyndon B. Johnson’s Great Society. 
 
 Within a few months after President Barack Obama took office in 2009, his administration had lined up support from health care providers, insurers, consumers and pharmaceutical makers by offering a grand bargain: The health bill would include a requirement that most Americans have health insurance, providing millions of new customers through the law’s often substantial premium subsidies and its option for states to expand Medicaid. In exchange, hospitals would have to accept spending cuts and the health care industry would have to accept new taxes to pay for the legislation. 
 
 The Obama White House dedicated enormous effort to win pledges of support before Democrats even put out a bill — an effort not replicated by the Trump White House or Republican leaders in Congress. 
 
 But the Affordable Care Act also created an array of taxes that the Republicans now hope to wipe away, helping them win the support of groups like the U.S. Chamber of Commerce and Americans for Tax Reform, led by the anti-tax activist Grover Norquist. 
 
 The congressional Joint Committee on Taxation issued estimates this week showing how much revenue the government could lose starting in 2018 under the Republican bill, which the party has called the American Health Care Act, as a result of repealing taxes on drug makers (nearly $25 billion over 10 years), insurers (nearly $145 billion), makers of medical devices (nearly $20 billion), and high-income households (more than $270 billion from taxes on earned income and investment income). 
 
 “The American Health Care Act repeals the medical device tax, which will result in greater investments in medical cures, lower health care costs and more high-tech manufacturing jobs in communities across the United States,” trumpeted the Medical Device Manufacturers Association.
– The GOP's replacement plan for ObamaCare isn't getting a universal thumbs-up, but it cleared one of its first hurdles early Thursday, the Hill reports. In a session that lasted more than 16 hours and went past 4am, the House Ways and Means Committee approved the measure in a 23-16 vote, with Republicans shooting down "off-topic" amendments proposed by Democrats, who in turn accused Republicans of trying to push the bill through while people were asleep and without a Congressional Budget Office analysis of the measure. "You're fearful the CBO will provide answers to questions that you don't like," such as bill costs or revealing who'd lose coverage, Michigan Rep. Sandy Levin said. One of the many bones of contention in the bill: a proposal to cut nearly $1 billion in CDC funding, per CNN. Committee Chair Kevin Brady said a "thoughtful, thorough comprehensive score" was expected before the bill ends up with the House Budget Committee, the next step in advancing the bill. Also pushing back on the controversial measure: groups representing retirees, hospitals, and medical professionals, the New York Times reports. The AARP and American Medical Association spurned the bill Tuesday, and on Wednesday, the American Nurses Association and lobbyist groups for hospitals and other health systems joined in, with the latter also mentioning the CBO's absence as an issue. "We are very concerned" the proposal "could lead to tremendous instability for those seeking affordable coverage," read a letter from the American Hospital Association and others. ABC News looks at the numbers needed to pass the legislation.