After years of insisting the Affordable Care Act was "rammed through" without Americans knowing what it would cost, House Republicans passed their own health-care plan on May 4, without an estimate of its impact from the Congressional Budget Office. (Jenny Starrs/The Washington Post)

House Republicans successfully voted to advance a major health-care bill Thursday afternoon without waiting for an official estimate of how the bill will affect the federal government's bottom line or how many Americans could go without insurance under the plan.

No one is sure whether the legislation would save the government money or add to the national debt. Congress's nonpartisan budgetary referees have not had time to put together their usual estimate of the costs and savings, and independent analysts are uncertain about what the results would be.

How many Americans' health insurance could be affected by the bill is also unclear. An earlier version of the legislation would have reduced the number of Americans with health insurance by 24 million, according to the referees at the Congressional Budget Office. Republicans have made changes to the bill to try to maintain coverage for some of those people, but analysts say there has not been enough time to analyze whether the revisions would achieve that goal.

“After I pick my jaw up, there’s just no conceivable way it makes sense to vote for or against something until you know what effects it would have,” said Maya MacGuineas, president of the independent Committee for a Responsible Federal Budget (CRFB). “These are really important issues in terms of the costs, the coverage, the incentives, and we want to get those things right. We can’t do it by flying blind.”

After Thursday's vote, the legislation moves to the Senate. Passing a health-care bill would allow Republicans to make good on their long-standing promise to repeal the Affordable Care Act. But they were unable to unite their party behind an earlier version of their Obamacare repeal effort and pulled the measure in March after it was clear they lacked the votes to advance it in the House.

That was the version analyzed by the CBO, which projected that the bill would save the government some $337 billion over 10 years.

Here are three big ways the new Republican bill might change health care in the United States. (Daron Taylor/The Washington Post)

There's a trade-off between the revised bill's cost and the GOP effort to reduce the number of people who would lose their insurance. The Republican plan — as did Obamacare — aims to make insurance affordable by giving government subsidies to help pay the premiums of many middle-class Americans who do not receive coverage through their employers. Because of those subsidies, if more people were able to keep their coverage under the new version, the government would have to spend more to help them.

The CRFB published an analysis Wednesday estimating the revised version of the bill could add to the federal deficit if the new bill would result in about 17.5 million people losing their insurance — that is, 6.5 million fewer than under the earlier version.

Other changes Republicans have made to the initial version of the bill include an additional $15 billion to reimburse insurance companies that take on unexpectedly costly patients, as well as $15 billion dedicated to health care for expecting mothers and newborns.

In all, those other changes would reduce savings in the bill to about $150 billion, according to the CRFB, but that figure does not include the additional costs associated with insuring more people.

“We are so far from having any real sense of what this would do for costs or coverage,” MacGuineas said. “There are no good numbers.”

Speaking on the House floor Wednesday, Majority Leader Kevin McCarthy (R-Calif.) said that a revised version of the earlier CBO estimate was not necessary.

“There is a CBO score out there right now on the bill,” he said.

That argument did not persuade Douglas Elmendorf, a former CBO director, who said that Republicans who opposed the previous version should wait for more-complete information before changing their votes.

“If you want to say the bill is just about the same, then I don’t see why more Republican members of the House would support it,” he said. “They are trying to persuade their members that it’s different enough that it should get more support, but they are not willing to wait for an actual estimate.”

The initial bill would have drastically reduced spending on Medicaid, the federal program that provides health insurance to poor Americans, saving the government about $880 billion over a decade, the CBO projected. The financing available to help middle-class households cover their premiums would also be reduced by about $310 billion, according to the initial estimate.

At the same time, the original Republican bill would have eliminated hundreds of billions in taxes that Obamacare imposed on wealthy households and on health-industry players such as insurers, pharmaceutical companies and manufacturers of medical devices.

Those provisions remain in the new plan, with the exception of a repeal of a tax Obama imposed on very wealthy earners. Under the version of the bill voted on Thursday, that tax would remain in place for five years to bring in more money in the interim.

Here are three big ways the new Republican bill might change health care in the United States. (Daron Taylor/The Washington Post)