Dean Heller (R), a key swing vote on the bill, who announced that he could not support it as written.
Nonetheless, Heller's announcement underscores the scant margin of error Republican leaders must deal with.
It "would have a profoundly negative impact on Americans", said John Meigs, president of the American Academy of Family Physicians.
The Congressional Budget Office will release its analysis of the bill next week.
Heller faces a hard re-election fight next year.
The provision would address concerns over the bill's current lack of penalties for those who choose not to purchase insurance, and could be introduced as soon as Monday, according to the report.
Also under the Senate proposal, insurers would be able to charge older customers more for their coverage than they could under the Affordable Care Act, the Washington Post reported.
The Senate legislation would phase out extra federal money Nevada and 30 other states receive for expanding Medicaid to additional low earners. Reducing taxes, Republicans argue, will boost the economy, and shrinking spending on programs such as Medicaid will slow the growth of the federal debt.
"I can not support a piece of legislation that takes insurance away from tens of millions of Americans and tens of thousands of Nevadans", Heller said.
■ Both the House and Senate health bills would fundamentally change the way the federal government pays its share of Medicaid costs, setting a per-person limit on spending that would adjust annually for inflation.
HORSLEY: But the Senate bill preserves another, more popular piece of Obamacare, the requirement that insurance companies cover everyone, even those with pre-existing conditions. But he said "it's going to be very hard to get me to a "yes" on the bill.
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Clinton wrote the strong words on Twitter as she retweeted a study by the Center for American Progress that said the health care bill now making its way through the Senate could lead to as many as 28,000 additional deaths in 2026. The main reason so many insurers are pulling out of the program is that Congress and GOP-dominated state governments refuse to live up to their end of the bargain.
Kansas' other senator, Republican Pat Roberts, has said he supports the bill and the Medicaid changes will not harm vulnerable populations. It would be politically hard for Heller to take a different stance on the measure from the popular Sandoval. Already, Democratic Rep. Jacky Rosen is preparing to challenge him.
The conservative quartet said they oppose the initial version, which will be subject to a slew of amendments during floor proceedings, for "a variety of reasons" but declared themselves "open to negotiation and obtaining more information before it is brought to the floor".
Four conservative senators have voiced their opposition but say they're willing to talk: Ted Cruz of Texas; Mike Lee of Utah; Ron Johnson of Wisconsin; and Rand Paul of Kentucky.
Underscoring the sensitivity of the bill, Sen.
Ernst declined to comment on any other provisions during a news conference at the Iowa Capitol, saying, "We have 142 pages to go through".
"It was just released yesterday".
"Part of what makes insurance work is everybody paying", she said.
AHCCCS Director Tom Betlach said if the cuts come to pass and the entire 400,000 new enrollees lose coverage, a cascade of problems are likely to follow similar to those that happened in a previous enrollment freeze. Iowa opted to expand, and has added more than 150,000 people to its rolls since 2014. The Senate parliamentarian will make that decision. If he can do it, McConnell then must spend the rest of the summer working with the House to see if they can pass the Senate bill, in whole, or negotiate a new compromise. Bernie Sanders, I-Vt., and MoveOn.org were planning weekend rallies in Pennsylvania, Ohio and West Virginia. Thirty-one states now offer Medicaid to this group.
Trump took to Twitter on Saturday to criticize the Affordable Care Act and Democrats who are opposed to the Republican repeal bill.
HSA savers: The Senate bill boosts the tax break for people in high-deductible plans in both the individual market and employer plans, by allowing them to put enough into their health savings accounts to cover much more of their out-of-pocket costs.
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