Updated August 2, 2021 at 10:49 AM ET

The Senate is poised to begin voting on a roughly $1 trillion bipartisan infrastructure package this week following a rare weekend session, culminating days and weeks of wrenching negotiations among a group of bipartisan lawmakers and President Biden.

The Infrastructure Investment and Jobs Act, which totals 2,702 pages, is part of what Democrats say is a two-track system to pass a bipartisan measure while also taking up a more ambitious spending bill they're driving.

Last week, Senate Majority Leader Chuck Schumer, D-N.Y., called for the Senate to remain in session this past weekend as the chamber awaited final text of the legislation.

"These days it isn't easy to do major bills in the Senate, especially bipartisan ones, so I've tried to prod the negotiators alone when they've needed it, and given them the space when they've asked for it," Schumer said in late-night floor remarks Sunday evening, moments before the legislative text was unveiled.

"In the end, the bipartisan group of senators have produced a bill that will dedicate substantial resources to repair, maintain and upgrade our nation's physical infrastructure," he said.

Schumer noted that it has been decades since Congress passed such a major, stand-alone investment in the country. He said the effort will help move America's infrastructure into "a new century."

It directs about $550 billion in new spending to address crumbling roads, bridges, broadband and the nation's power grid, among other efforts.

The legislation followed a framework set by the group of bipartisan lawmakers and the Biden White House. That framework drew an agreement from all sides weeks ago, but members had yet to hammer out the text of the bill.

Schumer said that text will provide the base of the bill, then the Senate will consider additional amendments this week. He predicted the Senate could process the amendments and approve it "in a matter of days."

He said once those votes are complete, the Senate will move to Democrats' much larger spending effort, a $3.5 trillion proposal, to address what some have called "human infrastructure." That measure includes funding for child care, tax breaks and health care — and there are efforts to include even more wide-reaching provisions on immigration reform.

However, the approach, which uses so-called reconciliation to dodge Republican opposition, faces a series of difficult obstacles. Among them, the Senate parliamentarian will be charged with whether to green-light the proposals.

Even if any of this legislation gains Senate approval, it must still head to the House, which is currently on recess through the rest of the month. House leaders have signaled they could return to take up the legislation, but Speaker Nancy Pelosi, D-Calif., has said they will not take up either of the two bills until both are ready, signaling a long, potentially months-long slog ahead.

Among the major new investments in the bipartisan package are:

There are also billions for airports, ports, broadband internet and electric vehicle charging stations.

The spending is broadly popular among lawmakers, bringing long-delayed capital for big-ticket items that cites and states can rarely afford on their own.

Paying for the package has been a challenge after senators rejected ideas to raise revenue from a new gas tax or other streams.

Instead, it is being financed from funding sources that might not pass muster with deficit hawks, including repurposing some $205 billion in untapped COVID-19 relief aid, as well as unemployment assistance that was turned back by some states and relying on projected future economic growth.

Bipartisan support from Republican and Democratic senators pushed the process along, and Schumer wanted the voting to be wrapped up before senators left for the August recess.

Last week week, 17 GOP senators joined all Democrats in voting to start work on the bipartisan bill. That support largely held, with Senate Minority Leader Mitch McConnell, R-Ky., voting yes in another procedural vote to nudge the process along in the 50-50 Senate, where 60 votes are needed to overcome a filibuster an advance legislation.

Whether the number of Republican senators willing to pass the bill grows or shrinks in the days ahead will determine if the president's signature issue can make it across the finish line.

Cornyn said he expects Schumer to allow all senators to have a chance to shape the bipartisan bill and allow for amendments from members of both parties.
"I hope we can now pump the brakes a little bit and take the time and care to evaluate the benefits and the cost of this legislation," Cornyn said.

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