Senators were back at work Sunday and laboring toward eventual passage of a $1 trillion bipartisan infrastructure package, with the Democratic leadership vowing to stay as long as it takes to overcome Republican holdouts who want to drag out final votes on one of President Joe Biden's top priorities.Majority Leader Chuck Schumer, D-N.Y., stressed to colleagues that they could proceed the "easy way or the hard way," while a few GOP senators appeared determined to run out the clock for days. "We'll keep proceeding until we get this bill done," Schumer said.The measure would provide what Biden has called a "historic investment" in public works programs — roads, bridges, broadband internet access, drinking water and more. In a rare stroke of bipartisanship, Republicans joined Democrats on Saturday to advance the measure. If approved, the bill would go to the House."We're on the cusp of seeing that move through the Senate," Transportation Secretary Pete Buttigieg said, citing "a remarkable coalition" that includes business, labor and lawmakers from both parties. "I think we're about to get this done."Despite that overwhelming support, momentum ground to a standstill when a handful of Republican senators refused to yield hours of required debate time before the next procedural votes. That opposition was delaying what supporters had hoped would be swift passage, and set up late night and early morning sessions in a dayslong slog. Final passage would be pushed to Tuesday.Sen. Bill Cassidy, R-La., a negotiator on the bill, said about 17 to 18 Republicans have indicated they support the bill, which would ensure eventual passage. "It could go quicker, but it's going," Cassidy said, adding, "And that's the good thing, it's going."Senators were meeting for the second consecutive weekend to work on the Infrastructure Investment and Jobs Act, the first of Biden's two infrastructure packages. Once voting wraps up, senators immediately will turn to the budget outline for a $3.5 trillion package of child care, elder care and other programs that is a much more partisan undertaking and expected to draw only Democratic support.Sen. Bill Hagerty, R-Tenn., an ally of Donald Trump and the former president's ambassador to Japan, was among those leading the effort to take as much time as needed to debate and amend the bipartisan bill."There's absolutely no reason to rush," Hagerty said during a floor speech Saturday. Trump issued a statement criticizing Biden, senators of both parties and the bill itself, though it was not clear whether the former president's views hold sway over the lawmakers.Biden, who was spending the weekend in Delaware, said the bipartisan package offers an investment on par with the building of the transcontinental railroad or interstate highway system. Overcoming the 60-vote hurdle was a sign that the tenuous alliance between Republicans and Democrats could hold on the public works package. In all, 18 Republicans joined Democrats on the 67-27 vote to push the measure past a filibuster.Senate Republican leader Mitch McConnell of Kentucky has so far allowed the bill to progress, despite the broadsides and name-calling coming from the former president. His vote Saturday — another "yes" — was closely watched. "This is a compromise," McConnell said.Senators have spent the past week processing nearly two dozen amendments to the 2,700-page package, but so far none has substantially changed its framework.More amendments could be debated Sunday with senators considering revisions to a section on cryptocurrency, a long-shot effort by defense hawks to add $50 billion for defense-related infrastructure and a bipartisan amendment to repurpose a portion of the untapped COVID-19 relief aid that had been sent to the states. Another key procedural vote was set for late Sunday.Senators have found much to like in the bill, even though it does not fully satisfy liberals, who view it as too small, or conservatives, who find it too large. It would provide federal money for projects many states and cities could not afford on their own.An analysis of the bill from the Congressional Budget Office drew concerns, particularly from Republicans. It concluded that the legislation would increase deficits by about $256 billion over the next decade. But the bill's backers argued that the budget office was unable to take into account certain revenue streams — including from future economic growth. Additional analysis released Saturday by the budget office suggested infrastructure spending overall could boost productivity and lower the ultimate costs.Paying for the package has been a pressure point throughout the months of negotiations after Democrats objected to an increase in the gas tax paid at the pump and Republicans resisted a plan to bolster the IRS to go after tax scofflaws.Unlike Biden's bigger $3.5 trillion package, which would be paid for by higher tax rates for corporations and the wealthy, the bipartisan package is funded by repurposing other money, including untapped COVID-19 aid, and other spending cuts and revenue streams.The House is in recess and is expected to consider both Biden infrastructure packages when it returns in September.Cassidy spoke on CNN's "State of the Union" and Buttigieg was on "Fox News Sunday." Associated Press writer Alan Fram contributed to this report.

A proposal to strengthen IRS enforcement to crack down on tax scofflaws and help fund a nearly $1 trillion bipartisan infrastructure spending is officially off the table, Republican Sen. Rob Portman said Sunday.Portman, who is involved in negotiating the bill, cited "pushback" from fellow Republican lawmakers who dislike the idea of expanding the reach of the IRS, which they have accused over the years of unfairly targeting conservatives. He said another reason the IRS provision was shelved is that Democrats are including a more robust enforcement plan in a separate $3.5 trillion infrastructure bill that they intend to pass through the Senate using special budget rules and without Republican votes."That created quite a problem because the general agreement is that this is the bipartisan, negotiated infrastructure package and that we will stick with that," the Ohio senator said on CNN's "State of the Union."Portman's announcement that the IRS provision had been removed underscores the difficulty facing the bipartisan group of Republican and Democratic senators in finding mutually agreeable ways to pay for billions of dollars of new spending their White House-backed plan calls for.Portman said meetings were planned Sunday to discuss alternatives to the IRS provision. Senate Majority Leader Chuck Schumer is pressuring lawmakers to reach an agreement this week on the pair of massive domestic spending measures, signaling Democrats' desire to push ahead aggressively on President Joe Biden's multitrillion-dollar agenda.Schumer, D-N.Y., said last week that he is scheduling a procedural vote for Wednesday to begin debate on the still-evolving bipartisan infrastructure bill. Senators from both parties, bargaining for weeks, have struggled to reach final agreement on a $1 trillion package of highway, water systems and other public works projects.Portman on Sunday called that an "arbitrary deadline" and one that was premature given that senators haven't even agreed on details of the "complex" bill yet."We want to get it right. It's not too much to ask that we have time to do that," Portman said. "We ought not to have an arbitrary deadline forcing this process."Schumer said he also wanted Democratic senators to reach an agreement among themselves by Wednesday on the specific details of a separate 10-year budget blueprint that envisions $3.5 trillion in spending for climate change, education, an expansion of Medicare and more.