WASHINGTON (NewsNation Now) — Congress Tuesday will once again face off on two looming economic crises in an effort to keep the government funded beyond a Thursday deadline and avoid defaulting on its debt.

Republican senators Monday blocked a bill to keep the government operating and allow federal borrowing, but Democrats aiming to avert a shutdown pledged to try again — at the same time pressing ahead on President Joe Biden’s big plans to reshape government.

Lawmakers now have just three days to avert a possible government shutdown by midnight Thursday. Failure to do so could furlough hundreds of thousands of federal workers in the middle of a national health crisis. The most recent shutdown in January 2019 lasted 35 days.

The efforts are not necessarily linked, but the fiscal year-end deadline to fund the government past Thursday is bumping up against the Democrats’ desire to make progress on Biden’s expansive $3.5 trillion federal overhaul.

It’s all making for a tumultuous moment for Biden and his party, with consequences certain to shape his presidency and the lawmakers’ own political futures.

“You know me, I’m a born optimist,” Biden told reporters Monday, as he rolled up his sleeve for a COVID-19 booster shot. “We’re gonna get it done.”

Monday’s 50-48 vote against taking up the bill fell well short of the 60 needed to proceed over a GOP filibuster. Democratic Majority Leader Chuck Schumer switched his vote to “no,” a procedural step to allow him to bring the measure back for consideration.

With days to go, Democrats said they will try again before Thursday’s deadline to pass a bill funding government operations past the Sept. 30 fiscal year end, stripping out the debate over the debt limit for another day, closer to a separate October deadline.

Meanwhile, the real action is unfolding behind the scenes over the $3.5 trillion measure, with Biden and his Democratic allies in Congress seeking a once-in-a-generation reworking of the nation’s balance sheets.

From free pre-kindergarten and child care subsidies for families with small children to dental care and hearing aids for seniors with Medicare, there’s a lot in the president’s proposal — all to be paid for with higher taxes on corporations and the wealthy.

With Republicans solidly opposed, Democrats are rushing to trim the total and win holdouts within their own party.

As the overall price tag comes down, Speaker Nancy Pelosi said the president is “working on that piece,” referring to talks underway with the Senate. Pelosi said the House Democrats would not move ahead on a bill until it is acceptable to their colleagues in the Senate. “We’re not there yet,” she said.

Building on a separate $1 trillion bipartisan public works package that’s already cleared the Senate and is heading for a House vote Thursday, Biden is seeking major spending for health care, education and efforts to tackle climate change. The total price tag, he contends, is actually “zero” — covered by the expected increase in tax revenue.

He is personally calling fellow Democrats in Congress in an effort to resolve differences and bring his sweeping domestic policy vision forward.

Ticking off the weighty list of goals along with meeting the other deadlines, Biden said, “If we do that, the country’s going to be in great shape.”

But Republicans say it’s real spending that can’t be afforded, and a reflection of the Democrats’ drive to insert government into people’s lives.

The bill Senate Republicans rejected Monday night would have funded government operations temporarily, to early December, while also providing emergency funds for Hurricane Ida and other disaster relief and for Afghan refugees.

Republican leader Mitch McConnell rejected that approach because Democrats also included a provision to suspend the debt limit, which would allow continued borrowing to pay off the nation’s bills.

McConnell has said he wants to fund the government and prevent a devastating debt default, but wants to force Democrats to split the package in two and take the politically uncomfortable debt ceiling vote on their own.

“Republicans are not rooting for a shutdown or a debt limit breach,” he said.

And so far, the bill is also too big for key Democrats whose votes are needed in the face of the GOP opposition. Two Democratic holdouts, Sens. Joe Manchin of West Virginia and Kyrsten Sinema of Arizona, have said they won’t support a bill of that size. Manchin has previously proposed spending of $1 trillion to $1.5 trillion.

Biden is expected to meet separately with Manchin and Sinema as he works to come up with a final number, according to a person familiar with the meetings and granted anonymity to discuss them.

Progressive lawmakers said they’ve already compromised enough with more centrist Democrats, but in one potential development, Rep. Pramila Jayapal, D-Wash., the chair of the Congressional Progressive Caucus, confirmed she and Sinema have been in talks.

Pelosi said she had yet to hear a new topline figure from Manchin or Sinema, but indicated that she expects talks to start moving swiftly toward a conclusion that would enable passage of Biden’s package as well as a companion $1 trillion public works bill.

“We have to see what comes of the negotiations that are going on — if they are worthy of the commitments we have made,” she said. “We will pass both bills.”

Biden’s proposal is to be paid for by increasing the corporate tax rate, from 21% to 26.5% on businesses earning more than $5 million a year, and raising the top rate on individuals from 37% to 39.6% for those earning more than $400,000 a year, or $450,000 for couples.

While Democrats are largely in agreement on Biden’s vision — many ran their campaigns on the longstanding party priorities — stubborn disputes remain, including how to push toward cleaner energy or to lower prescription drug costs.

With all Republicans opposed, Democratic leaders can’t spare a single vote in the 50-50 Senate, relying on Vice President Kamala Harris to break a tie to pass the eventual package.

All this comes as other deadlines swirl this week to pay for government operations and allow more borrowing or risk a devastating federal shutdown or debt default — though those dire scenarios appear unlikely.

Schumer called the Republican opposition “unhinged.”

“The Democrats will do the responsible thing — the right thing, the thing that has been done for decades by both parties — and vote yes,” said Schumer ahead of the vote.