WASHINGTON (AP) — The Senate Republican health care bill would leave 22 million more Americans uninsured in 2026 than under President Barack Obama's health care law, the Congressional Budget Office estimated Monday, in a blow to GOP leaders' hopes of pushing the plan through the chamber this week.

The CBO coverage estimates pose yet another problem for Senate Majority Leader Mitch McConnell, R-Ky., who unveiled the legislation last Thursday. By Friday afternoon, he was facing public statements of opposition from five GOP senators — three more defections than he can afford and still win approval for the legislation over united Democratic opposition. Others have expressed concerns.

The 22 million additional people without coverage under the Senate proposal is just a hair better than the 23 million who'd be left without insurance under the measure the House approved last month, the budget office has estimated. President Donald Trump has called the House version "mean" and called on Senate Republicans to approve legislation with more "heart."

Of the 22 million, 15 million of them would have no insurance next year, the nonpartisan budget office said. That could be a particular concern to Sen. Dean Heller, R-Nev., who faces perhaps the toughest 2018 re-election race of any Senate Republican and who's said he can't support a health care package that cuts Medicaid like the GOP plan and takes coverage from "tens of millions of Americans and tens of thousands of Nevadans."

Sen. Susan Collins, R-Maine, and several other moderate GOP senators have also expressed concerns about the measure's impact on coverage. On the other hand, four conservatives have said they oppose the current version of the bill for not doing enough to reduce premiums.

The budget office report said it believes the Senate bill "would increase the number of uninsured people substantially. The increase would be disproportionately larger among older people with lower income" — especially those between 50 and 64 and with incomes below 200 percent of the poverty level, or around $30,300 for a single person. Those ages are just shy of when people begin qualifying for Medicare coverage.

Earlier Monday, Republican leaders added a penalty to their bill for people who've had at least a 63-day gap in coverage during the past year. Under that proposal, if they then buy insurance, they would face a six-month delay before it takes effect. The budget office said its estimate included the impact of that addition.

The change was aimed at helping insurance companies and the insurance market by discouraging healthy people from waiting to buy a policy until they get sick. Insurers need healthy customers who are inexpensive to cover to help pay the costs of people with medical conditions that are costly to treat.

The Senate bill would roll back much of Obama's health care overhaul. His statute pressures people to buy insurance by imposing a tax penalty on those who don't, but the Republican legislation would repeal that penalty, effectively erasing Obama's so-called individual mandate.

The House approved its legislation in May. It would require insurers to boost premiums by 30 percent for those whose coverage lapsed.