The Senate is slogging through an overnight session that has dragged into Tuesday, with Republican leaders buying time as they search for ways to secure support for President Donald Trump's big bill of tax breaks and spending cuts while fending off proposed amendments, mostly from Democrats trying to defeat the package. Senate Majority Leader John Thune of South Dakota is working for a last-minute agreement between those in his party worried the bill's reductions to Medicaid will leave millions without care and his most conservative flank, which wants even steeper cuts to hold down deficits ballooning with the tax cuts.