But senators have said they've been told the bill contains an additional $45 billion in funding for opioid addiction treatment, a particularly important priority for Collins and other holdouts like Sen.
Underscoring the uncertainty, No. 3 Senate GOP leader John Thune of South Dakota would not make predictions about the health care vote.
"I will be very angry about it" if the bill collapses, Trump said.
But McConnell faces hurdles in his quest, including recalcitrant members of his caucus pulling in opposite directions, a unified Democratic opposition, and to need to meet the strictures of a Senate rule that would allow him to pass the bill with a simple majority. The announcement comes as disagreements within the Republican Party have delayed an overhaul of the US health-care system and threatened to set back other action, like raising the debt ceiling, passing an appropriations bill or approving a tax reform plan.
Senate Republican leaders are adding new language to their health care bill to allow the sale of cheap, bare-bones insurance plans in an attempt to draw enough conservative support to pass the measure to replace Obamacare. But major changes to the Medicaid provisions in the bill are not likely.
A revised Congressional Budget Office score, showing the costs and impact on coverage of the new version of the bill, is expected on Monday or Tuesday of next week. Sens. Ted Cruz, R-Texas, and Mike Lee, R-Utah, have an amendment which would let insurance companies sell any health insurance plan they wish as long as they also offer at least one plan that is compliant with all of the coverage mandates outlined in Obamacare.
Voelkel declined to say if Johnson is committed to vote for the bill.
In a written statement, McConnell said the chamber would use that time to work on health care, defense and some of President Donald Trump's nominations.
"We're going to do healthcare next week", McConnell told reporters.
U.S. Sen. Lindsey Graham scooped Senate Republican leaders Thursday, unveiling his own plan for health-care reform before GOP leaders had a chance to unveil their revised proposal to repeal Obamacare.
Moderate Republicans, meanwhile, should appreciate that Graham and Cassidy's plan keeps requirements that individuals with pre-existing conditions can't be denied care.
Paul, who was a hard "no" on the first version, said "the new bill is the same as the old bill, except for worse".