Rand Paul of Kentucky, who has rejected the plan along with fellow Republican Senators Ted Cruz of Texas, Mike Lee of Utah and Ron Johnson of Wisconsin, said fundamental problems still remain that would leave taxpayers subsidizing health insurance companies.
The Congressional Budget Office issued a report in May saying by 2026, 28 million people would be uninsured under Obamacare and 51 million would be uninsured under the American Health Care Act, the bill House Republicans passed last month.
Some GOP senators are not so sure about that.
Sen. Dean Heller, R-Nev., who faces a competitive re-election race in 2018, says he has "serious concerns about the bill's impact on the Nevadans who depend on Medicaid".
The Senate's plan, like one passed by the House of Representatives, rolls back numerous provisions of Obamacare, including taking deep cuts from Medicaid program.
The four Republican holdouts, among the Senate's most conservative members, said the plan did not go far enough in scaling back the federal government's role, highlighting Republicans' struggle to craft legislation to revamp a sector that accounts for one-sixth of the world's largest economy. "It's so devastating to the middle class", he said on ABC, putting the Republicans' chances of passing the current bill at "50-50". That would focus the aid more on people with lower incomes than the House legislation, which bases its subsidies on age.
Senate Republicans have little margin for error as they prepare for a vote this coming week on a bill to repeal and replace the Affordable Care Act.
The number of Republicans opposing Mitch McConnell's Obamacare repeal bill continues to grow.
Ben Sasse said Sunday the Senate's current plan to overhaul health care "is not a full repeal or full replace".
Medicaid provides health care not just for the indigent and disabled but also for the working poor - low-wage employees who can not afford health insurance, even the plans offered through their jobs.
Arizona's Republican Gov. Doug Ducey said Friday the Senate GOP bill falls short of what his state needs. It would be politically hard for Heller to take a different stance on the measure from the popular Sandoval.
"Sen. McConnell has said that he wants a vote next week and that's up to him to run the chamber the way he sees fit".
Trump later criticized the House bill privately as "mean" and this week called for a health plan "with heart".
"As I have consistently stated, if the bill is good for Nevada, I'll vote for it and if it's not - I won't", Heller said.
Lynch said the shift in Medicaid funding - from 50-50 state and federal funding to roughly 70 percent funded by states - will be particularly devastating to states that took advantage of Obamacare's Medicaid expansion in recent years, including MA, saying: "Medicaid expansion, that'll kill MA". Iowa opted to expand, and has added more than 150,000 people to its rolls since 2014. "It's simply not the answer", he said at a news conference, CNN reports.
Now he's facing his next challenge - persuading enough Republicans to back the measure.
President Donald Trump is bemoaning what he calls "the level of hostility" that he says has stymied bipartisanship in Washington. But a defeat would be a bitter and damaging blow to Trump and his party.
CBO analysis of the bill predicts that 23 million Americans would lose their health insurance, while the top 1 percent of Americans would enjoy $306 billion in tax cuts over 10 years.
Medicaid is the means to independence for millions of children, seniors and adults with disabilities and their families.