McConnell has said he was willing to make changes to win support, and in the week ahead, plenty of backroom bargaining is expected. The bill will fail if just three of the 52 Republican senators oppose it, an event that would deal a humiliating blow to President Donald Trump and Senate leaders.
But Cassidy, a physician, says he still has concerns about the bill in its current form.
Earlier Monday, a conservative Republican senator used unusually harsh terms to accuse party leaders of trying to rush the party's health care bill through the Senate. But they won't, because the tax cuts are the thing that matters to them.
Sen. Chris Murphy (D-Conn.) described the bill as a "humanitarian catastrophe waiting to happen". "No way", Johnson said on NBC's Meet the Press.
McConnell drafted the plan behind closed doors after numerous meetings among GOP senators.
"It seems highly likely", Madara wrote, that the changes "will expose low and middle income patients to higher costs and greater difficulty in affording care". He criticized the measure for increasing federal spending on subsidies for people buying coverage and not eliminating enough of Obama's regulations on insurers, including protections for consumers with pre-existing medical conditions.
Of the 22 million without coverage by 2026 under the Senate plan, 15 million would be without it next year, the budget office said.More news: Budget Office: Senate Health Bill Adds 22 Million Uninsured
Trump toned down the Fox News reporter's question, saying, "I don't see him leading it". President Donald Trump has called the House version "mean" and called on Senate Republicans to approve legislation with more "heart". All they do is delay and complain.
He went on to say that Democrats have become "obstructionists", and that it's a "terrible theme for the people of this country". Especially when Obamacare's modest problems could be fixed with nothing more than a few minor changes and additional funding of $5-10 billion or so.
She said she intends to wait for a Congressional Budget Office analysis before making a decision.
A number of Republican senators have said they have reservations about the US Senate's healthcare overhaul and do not think it will be able to pass this week.
"We have been disappointed that movement has not been more dramatic toward a full repeal", said president of Americans for Prosperity (AFP) Tim Phillips.
As more analysis of the bill reached state officials, especially in places that expanded Medicaid access under the Affordable Care Act, misgivings grew. And it would put annual caps on overall Medicaid money the government until now has automatically paid states, whatever the costs.
In contrast, Democrats argue that Obamacare has helped some 20 million Americans while citing other benefits they believe have occurred, such as better preventive care. Ted Cruz (Tex.), Dean Heller (Nev.), Mike Lee (Utah), and Rand Paul (Ky.) have all announced they will not vote for the bill.
"I think the President is very supportive of the Senate bill", Spicer said.