Senate GOP leaders hope offering more money for reducing insurance premiums for poor people is enough to get centrists to support their healthcare bill after they were cool to the latest version.

Republican leadership released a new version of the healthcare bill that adds $70 billion to a stability fund to stabilize the individual market and $45 billion for fighting opioid abuse. However, leadership faces a monumental task of winning support from several key centrists, especially after leaving in place more than $700 billion in Medicaid cuts.

They also are facing lingering conservative opposition and some members champing at the bit to file amendments to change the legislation.

While several changes to the bill were enough to get hardline conservative Sen. Ted Cruz, R-Texas on board, centrists were more skeptical.

"I want to make sure that with regards to those people who are currently getting coverage under Medicaid expansion there are some options for them," said Sen. Rob Portman, R-Ohio, a key centrist vote.

Portman is undecided on whether to vote for a procedural motion to advance the bill in the Senate. Republican Sens. John Hoeven, of North Dakota, Shelley Moore Capito of West Virginia, and Dean Heller of Nevada also said they haven't decided.

Sens. Rand Paul, R-Ky., and Susan Collins, R-Maine, already said they would vote against the procedural motion, meaning Senate Majority Leader Mitch McConnell can't afford to lose any more Republican senators.

McConnell held a closed-door meeting Thursday afternoon with Capito, Heller, Hoeven, Portman, and Alaska Sens. Lisa Murkowski and Dan Sullivan, among others. The focus was on Medicaid, and Centers for Medicare and Medicaid Services Administrator Seema Verma attended.

Murkowski told reporters after leaving the meeting that a provision in the new bill is aimed at Alaska. The provision, first reported by the Business Insider, gives states more stability funding if the cost of insurance premiums is at least 75 percent higher than the national average.

A report from the federal government showed that Alaska would be the only state to meet that criterion.

Murkowski, however, told The Hill that she remains undecided on the bill. The new version would defund Planned Parenthood for a year, a move Murkowski has said she opposes.

The bill leaves in place about $770 billion in cuts to Medicaid and a three-year phase out of the Medicaid expansion starting in 2020.

Centrists have been worried about the impact of the cuts on their states, especially those who live in states that expanded Medicaid under Obamacare.

Some senators say there has been talk of giving refundable tax credits to potential Medicaid beneficiaries to compensate for any cuts.

"States are already buying people Medicaid policies so we are expanding on that using the refundable tax credit to do that," Hoeven said after the meeting.

However, the Senate bill would keep the same structure for refundable tax credits.

The bill's credits can help customers pay for premiums for plans that require insurers to cover 58 percent of the costs, as opposed to under Obamacare where the credits go to plans that cover 70 percent of the costs.

Hoeven said lawmakers could change the tax credit structure or put more money into the long-term stability fund to "pay the difference" among the two measures. When asked which route he prefers, Hoeven responded he likes "whichever works better and gets it done."

"This is why we need to see the numbers," he added, referring to a score from the nonpartisan Congressional Budget Office. The score, expected early next week, would determine how the bill would affect spending and insurance coverage.

The bill must reduce the deficit by about $111 billion for Republicans to use a procedural move called reconciliation that lets a bill be approved in the Senate with only 51 votes.

The CBO score for the previous version estimated that 22 million people would go without insurance for the next decade.

The new version includes an additional $70 billion for the stability fund and keeps Obamacare's taxes on investments and a Medicare surtax, giving Republicans more funding to work with. It also includes $45 billion to fight opioid abuse, a key request from centrists.

"The $45 billion is progress, no question about it," Portman said.

Portman and Capito also said that they want to see what the CBO says about the bill. Senate leadership hopes to take a procedural vote early next week.

But it may be that the centrists aren't McConnell's only problem.

The majority leader thought he shored up his conservative flank after including a version of an amendment drafted by Sens. Mike Lee, R-Utah, and Ted Cruz, R-Texas. The amendment would let insurers sell plans that don't comply with Obamacare's insurer mandates as long as they sell some plans that do.

While a majority of the amendment was included, not all of it was. That miffed Lee, who said he is undecided on the bill.

Lee said he doesn't think much has changed from the initial version of the bill, which he opposed.

A spokesman for Lee tweeted that the bill keeps Obamacare's regulation for a shared risk pool between individual and small group markets. People who don't have insurance through work use the individual market, and small businesses use the small group market.

Members of Senate leadership left a mid-morning briefing outlining the new bill saying they were confident they are making progress.

Sen. John Thune, R-S.D., said, when asked about the bill's chances with centrists, that there would be opportunities for senators to file amendments.

The centrists aren't the only ones looking to add to the bill.

"The revised Senate healthcare bill released today does not include the measures I have been advocating for on behalf of the people of Arizona," said Sen. John McCain, R-Ariz., in a statement. He said he would file amendments to address concerns from state lawmakers such as Gov. Doug Ducey on Medicaid. He then gave a bit of foreshadowing on what will happen next if the Senate bill fails.

"If we are not able to reach a consensus, the Senate should return to regular order, hold hearings and receive input from senators of both parties, and produce a bill that finally provides Americans with access to affordable and quality healthcare," he said.