(Bloomberg) About 24 million more people would be uninsured under the Republican plan to replace Obamacare, according to the nonpartisan Congressional Budget Office, creating a daunting political impediment for a proposal that would reduce the deficit by more than $300 billion.

The coverage estimate is a setback for President Donald Trump, who promised that “insurance for everybody” would replace Obamacare, which used government subsidies and an expansion of Medicaid to bring coverage to 20 million people. But Republicans, who have said they will do the health overhaul in three phases starting with the bill to repeal and replace pieces of Obamacare, are pushing back on the numbers.

“The CBO looked at a portion of our plan, but not the entire plan,” Health and Human Services Secretary Tom Price told reporters outside the White House after the CBO estimate was released.

“We disagree strenuously with the report that was put out,” Price said. “We believe that our plan will cover more individuals at a lower cost and give them the choices that they want, the coverage that they want for themselves and their families.”

Republicans trying to pass the legislation without Democratic support argued that any reduction in the rolls of the insured isn’t as important as what they say will be cheaper coverage. House Speaker Paul Ryan said there will be a stable transition if the bill is passed so “no one has the rug pulled out from under them.”

“Our plan is not about forcing people to buy expensive, one-size-fits-all coverage,” Ryan said in a statement. “It is about giving people more choices and better access to a plan they want and can afford.”

But some Republicans said the CBO estimate suggested that the party needed to rethink its current Obamacare plan.

“If half of what they are saying is true, then we ought to slow down and get this right,” Republican Senator Lindsey Graham of South Carolina told reporters after the estimate came out. “Rather than attacking the CBO as a way of moving forward, I think the prudent thing for the party to do is to look at the CBO report and see if we can address some of the concerns raised.”

Ceci Connolly, chief executive officer of the Alliance of Community Health Plans, said it may be time for lawmakers to go back to the drawing board.

“No one wants to see America move backward in pursuit of high-quality, affordable health care,” Connolly said in a statement. “It’s time to take a step back and thoughtfully consider viable alternatives.”

Insurance premiums will be 15 percent to 20 percent higher over the next couple of years, before the GOP replacement plan goes fully into effect, the CBO estimated. They’d fall after, thanks to more young people signing up and a provision in the bill that lets insurers offer fewer benefits, the CBO says. In a decade, premiums are estimated to be 10 percent lower than they would have been under Obamacare.

The CBO said the GOP proposal would reduce the deficit by $337 billion over 10 years.

Democrats quickly used the CBO scores to attack the GOP plan. Senator Ron Wyden, an Oregon Democrat, said the report shows "Trumpcare is an awful deal for the American people."

“This should be a looming stop sign for the Republicans repeal effort,” said Chuck Schumer, the Senate’s Democratic leader.

Trump touted the plan Monday before the CBO score was released.

“More competition, less regulation will finally bring down the cost of care,” Trump said. “It takes a while to get there because you have to let that marketplace kick in and it is going to take a little while to get there. Once it does, it is going to be a thing of beauty.”

Medicaid Reduction

The coverage losses would begin even before many parts of the Republican plan go into effect. The CBO estimates that next year about 14 million fewer people would have insurance, largely because they’d no longer choose to buy it. The losses in coverage after 2018 mainly come from Medicaid, CBO said. By 2026, about 52 million people would be without health insurance. If the Affordable Care Act instead continued, 28 million would be uninsured.

The American Medical Association, which already said it opposes the AHCA, called the coverage losses under the plan "unacceptable."

“The AMA believes we need continued progress to expand coverage for the uninsured,” Andrew Gurman, the doctor group’s president, said in a statement. “We hope the CBO estimates will motivate all members of Congress to find a pathway to work together on significantly improving [the] proposed health reform legislation.”

Ryan is trying to skirt opposition from the conservative wing of the party, which has derided the measure as “Obamacare Lite,” and moderates facing angry constituents who face losing care. Several key Republican senators have said they can’t vote for the bill in its current form. Ryan has tried to steel party members against the office’s estimate.

“I’ve been telling our members, just get ready, this is always what happens with CBO,” Ryan told radio host Hugh Hewitt on Friday. “You’re never going to win a coverage beauty contest when it’s free market versus government mandates.”

The push to kill the Affordable Care Act comes after seven years of quixotic votes against it, each vetoed by President Barack Obama. Republicans have said throwing out the law would fulfill key campaign promises and set the stage for a broad rewrite of the tax code. But the measure faces opposition from top trade groups for physicians and hospitals, who say it will leave more people uninsured or with limited coverage. And many in the newly empowered GOP are having second thoughts now that they will be blamed for any failures.

Tax Credits

The legislation, called the American Health Care Act, repeals Obamacare’s mandate that everyone must have insurance or pay a penalty. It also provides age-based tax credits to help people purchase coverage, though they’re lower than the income-based subsidies offered under current law. The bill will also wind down Obamacare’s expansion of Medicaid in 2020. About 12 million people gained coverage in the 31 states that expanded Medicaid.

The cost of the new tax credit for health insurance to be established in 2020 is estimated at $361 billion through 2026, according to the CBO. The biggest spending reduction comes from Medicaid, where the CBO estimates funding will be reduced by $880 billion over a decade. That would lead to about a 17 percent reduction in Medicaid coverage, or 14 million fewer people covered by the program by 2026.

Planned Parenthood would also lose $234 million in funding, and the CBO projects that would reduce access to services aimed at helping women avert pregnancies. Several thousand additional babies will be born because of the lack of access to birth control, the office estimated, costing Medicaid $77 million over a decade.

Two key House committees approved the act on Thursday after marathon sessions in which Democrats offered amendments rejected by Republicans. The bill will head next to the Budget Committee as early as Wednesday before being considered by the full House of Representatives.

Republicans who have downplayed the CBO’s role point out that the office overestimated by several million the number of people who would sign up for insurance through the Obamacare marketplaces.

“They have been woefully underperforming when it comes to evaluating health systems,” Price said Friday on MSNBC. “And that’s not because they are bad folks. It’s because this is challenging stuff.”

Previous Praise

Still, the CBO did correctly predict other aspects of Obamacare, including premium levels and the cost of subsidies to help people buy insurance, said Douglas Elmendorf, CBO director when the office estimated the effects of Obamacare, which Congress passed in 2010.

Republicans hand-picked the current CBO director, Keith Hall. And Price, who was involved in his selection, praised Hall in April 2015, after he and other congressional Republicans had just installed him in the post.

“Keith Hall will bring an impressive level of economic expertise and experience to the Congressional Budget Office,” Price said in a statement at the time. He went on to note Hall’s background in providing Congress with nonpartisan economic analyses at the U.S. International Trade Commission. Hall also served as chief of George W. Bush’s Council of Economic Advisers.

“His vast understanding of economic and labor market policy will be invaluable to the work of CBO and the important role it will continue to play as Congress seeks to enact policies that support a healthy and growing economy,” Price had said.

- With assistance from Steven T. Dennis, Arit John, Toluse Olorunnipa, Erik Wasson and Billy House

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