Republicans are struggling to devise a solution to the health care problem their package has created. Already, estimates say 10.9 million more people would be without health coverage under the House-passed version of the bill. GOP senators have proposed steeper reductions, which some say go too far.

The Senate parliamentarian has advised that a Medicaid provider tax overhaul central to President Donald Trump’s tax cut and spending bill doesn’t adhere to the chamber’s procedural rules, delivering a crucial blow as Republicans rush to finish the package this week.