McConnell has little time to make a deal. Republican leaders have said they need to move on to other issues, including a tax-code overhaul and next year’s spending bills, if they can’t agree on a health bill before a month-long August break.

For the bill to pass, and Republicans to live up to their promise to eliminate President Barack Obama’s signature domestic accomplishment, they can lose no more than two GOP votes from their 52-48 majority amid unanimous Democratic opposition.

Republicans say they’re increasingly pessimistic the GOP legislation can win approval.

Senator Bill Cassidy of Louisiana said on “Fox News Sunday” that McConnell’s original plan is dead and that what happens with the rewritten version remains to be seen. He put the odds of passing a bill in July at “50-50.”

Given the lack of support for McConnell’s legislation, Senator John McCain of Arizona said on CBS’s “Face the Nation” that Republicans should write a new bill and let Democrats offer amendments. “That’s what democracy is supposed to be all about,” he said.

McConnell himself took a risk on Thursday by calling for a bipartisan health-care plan if the Republican-only bill fails. He told an audience in his home state of Kentucky that the Affordable Care Act needs to be altered, as insurers are pulling out of some areas.

McConnell’s message could serve as a warning to holdout conservative Republicans most ideologically opposed to Obamacare, but the remarks also may give wavering moderates cover to oppose the GOP plan.

The Trump administration is taking a more optimistic view on passing a bill. The Senate may delay its August recess to finish the health-care overhaul, White House Chief of Staff Reince Priebus predicted on “Fox News Sunday.”

McConnell is awaiting estimates from the Congressional Budget Office of possible changes to his bill to determine whether they would increase spending or alter estimates of the number of people who would lose their health coverage. The CBO said the initial proposal from McConnell would cause 22 million fewer Americans to have health insurance in a decade.

"Discussions about the legislation continue within the conference and with CBO,” said David Popp, McConnell’s spokesman.

Republican leaders are considering axing plans to repeal nearly all of the tax increases that help finance the Affordable Care Act, said the GOP aide. The GOP health bill may retain a 3.8 percent investment tax on high-income earners and a Medicare earned-income surcharge on the wealthy.

Medicaid changes

Those two tax increases generate nearly $231 billion in revenue over a decade, according to the Joint Committee on Taxation. Leaving them in place could create a way to cover the costs of expanded Medicaid coverage for the poor or other programs demanded by holdout moderate Republicans.

Related: Disability advocates fear impact of Medicaid cuts

There likely will be changes to the Medicaid provisions in McConnell’s earlier proposal based on feedback from senators, the aide said. These changes are proving to be among the most difficult to negotiate as GOP senators have vastly different requests based on their states’ needs, the aide said.

The aide said a revised bill probably will boost proposed spending to stabilize premium costs in Obamacare’s insurance exchanges, where those without employer- or government-provided coverage can buy individual policies.

McConnell’s earlier legislation includes $50 billion over four years to bolster insurance markets, in addition to added cost-sharing subsidies. It also includes a state innovation pool of $62 billion over eight years that would allow jurisdictions funding for high-risk pools, reinsurance and other items.

During the week-long congressional recess, Republican lawmakers who held public appearances got an earful on the GOP’s bill, which polls show has attracted little public support.

‘Stepping on the necks’

At a town hall meeting in Baton Rouge, one Louisiana man told Cassidy that cutting health care for 22 million Americans is akin to “stepping on the necks” of his constituents.

Senator Jerry Moran of Kansas told constituents who expressed opposition to the GOP health plan at a gathering in Palco that he would demand the bill address the needs of people with pre-existing conditions and lower premium costs. “That’s not where we are with the legislation pending in the Senate,” he said.

Senator Susan Collins of Maine told the Washington Post after a July 4 parade that people were encouraging her to stand against the Senate bill and the House’s version of health legislation that passed in May.

“People were thanking me, over and over again,” she told the Post. “‘Thank you, Susan!’ ’Stay strong, Susan!’"

Opioid epidemic

McConnell’s early attempts to win over opponents haven’t worked. GOP leaders agreed more than a week ago to add $45 billion in spending to address the opioid epidemic, a key demand of moderates like Rob Portman of Ohio and Shelley Moore Capito of West Virginia.

Related: Opioid prescriptions ebb but addiction, overdoses still vex U.S.

After a tour of a suburban Cincinnati drug recovery center last week, Portman told an Associated Press reporter that the addition of those funds is but a first step. "I’m still concerned about the way in which Medicaid is dealt with in the proposal," Portman said.

Republican leaders are considering a provision proposed by Senator Ted Cruz, a Texas Republican, that a group of conservative GOP senators say could help gain their support. Cruz wants to allow insurers to offer cheap, bare-bones plans alongside those that meet the more comprehensive coverage requirements of Obamacare.

Critics in both parties say the proposal would essentially put people with pre-existing conditions in the Obamacare insurance pool and allow young, healthy people to buy cheaper plans in a separate pool.

Two Republican aides said GOP leaders asked the CBO to examine the impact of Cruz’s plan alongside a companion piece that would boost money to stabilize the exchanges.

The conservative Club for Growth is calling on McConnell to include Cruz’s insurance proposal, and to also repeal Obamacare’s net investment income tax. Without those two demands, the best result would be for McConnell to simply seek to repeal Obamacare, Club for Growth president David McIntosh said in a statement.

If McConnell can’t salvage his legislation, “the next best option would be to pass a real repeal bill as a standalone,” McIntosh said.

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