Many Republican senators dismissed the idea of overruling the Senate parliamentarian after she rejected key Medicaid provisions in Trump's tax and immigration bill Thursday, which dealt a blow to Republicans' plan to slash costs in the budget package.

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.