The White House and senators from both parties are scrambling to pull their infrastructure talks back from the point of collapse, a sudden turnabout after key negotiators expressed confidence they were nearing a final deal.

If the talks on the $1.2 billion framework fall apart, it would deal a serious blow to White House hopes of securing a bipartisan deal, an important political win for President Biden and moderate Democrats in the House and Senate. Several Republicans have also put their reputations on the line to get a deal.

Senators and the White House were both trying to tamp down the doomsday predictions Monday evening amid finger-pointing on both sides.

Sen. Rob Portman (Ohio), the lead GOP negotiator for the talks, told reporters early Monday evening that their coverage had been too pessimistic.

“‘Oh, it’s terrible. Everything is falling apart,’” Portman said, offering his impression of how reporters are covering the negotiations. “[But] it’s good. We’re making progress. ... Somebody be a little positive. I mean, c’mon.”

Sen. Jon Tester (D-Mont.), who had said earlier Monday that he thought the talks had slowed, appeared more optimistic after the Democratic negotiators met with Senate Majority Leader Charles Schumer (D-N.Y.).

“I feel bullish that it will be done by the morning,” Tester said, referring to Tuesday. “Is there still outstanding issues? Yeah. Nobody’s bailed.”

The bipartisan group met on Monday evening to try to salvage the deal after an intense day of fighting appeared to put it on shaky grounds and seemed optimistic after their talk. The senators are expected to talk late into Monday night by phone.

"Hell no. We're not pulling the plug," said Sen. Joe Manchin (D-W.Va.) about the talks. "We're trying to get the best infrastructure bill, with bipartisan movement ... and we're hoping to get that done."

Sen. Mitt Romney (R-Utah) said the group was "making good progress, and I'm confident that we're going to get to a deal. ... Our group here is seeing eye to eye."

The White House and Biden positioned themselves as hopeful. Biden described himself as “optimistic,” while White House press secretary Jen Psaki described the talks as in the “end stages.”

“We remain confident in reaching an agreement and we also remain interested in any Republican counteroffers,” she said.

Some said the drama was typical of the last-minute wrangling that happens toward the end of negotiations, with all sides trying to use their leverage to get the best deal possible. Portman chalked up the hurdles to being “the way it goes” on big deals.

While Portman on Monday said the deal was 90 percent done, multiple sources said the group faces a laundry list of unresolved issues.

Besides funding for public transit, there are differences over money for broadband, highways and bridges; using unspent COVID-19 relief funds to help pay for the bipartisan deal; and Republicans wanting to waive federally mandated wage requirements for federally funded projects.

The two sides also scuffled Monday over water funding.

Democrats are concerned the bipartisan deal won’t fully fund a water bill previously passed by the Senate or provide an additional $15 billion for treating water contamination caused by lead pipes and accused Republicans of proposing something “completely unworkable.”

In a reflection of the bitterness on display Monday, Democrats accused Romney of walking away from a deal on the water-funding portion and moving the goal posts. Romney's office called the accusation “laughably false” and accused Schumer of requesting an additional $15 billion in funding.

Schumer and the White House made Republicans a “global offer” on Sunday night that Democratic sources described as offering a solution for all of the points of contention. But a Republican aide circulated a list of “broken agreements” they believed had been included in the Democratic offer. And a second GOP source familiar called the offer “discouraging” and said it reopened issues that the bipartisan group had already agreed to.

Schumer, speaking from the Senate floor on Monday, stressed that he and Democrats are still committed to getting a bipartisan deal but argued that after weeks of negotiating, it was time to clinch a final agreement.

“We have reached a critical moment. The bipartisan group of senators has had nearly five weeks of negotiations since they first announced an agreement with President Biden. It’s time for everyone to get to ‘yes’ and produce an outcome for the American people,” Schumer said.

Manchin said he didn't see the offer until Monday. And Tester also downplayed that the “global offer” had thrown a wrench into hopes for an agreement.

“That’s what’s done when you get to a point where you get fish or cut bait, and that’s what they were doing. It’s fine. Everything is good on that,” he said.

Democrats are under pressure to quickly make progress on Biden’s sweeping infrastructure package. They are pursuing that along two paths: the $1.2 billion bipartisan negotiations and a separate $3.5 trillion bill they want to pass under a budget process that will let them avoid needing GOP votes for the larger bill.

"There reaches a point if you can’t reach an agreement you have to be honest about it," said Sen. Dick Durbin (Ill.), the No. 2 Senate Democrat.

But if the bipartisan deal fails, that could complicate Democrats’ ability to pass a budget resolution that sets up the larger deal. In the Senate they would need all 50 Democratic votes in order to pass the budget resolution, and several moderates, including Manchin and Kyrsten Sinema (D-Ariz.), haven’t yet committed to supporting the budget resolution.

Manchin indicated that he viewed getting a bipartisan deal as necessary if Democrats are going to be able to pass their party-line bill.

"I would say that if the bipartisan infrastructure bill falls apart then everything would fall apart," Manchin said. "Both of them are extremely important. Well if one falls apart, how do you do the other one?"

Schumer has vowed that he will give both the bipartisan deal and the budget resolution a vote before leaving town.

In an apparent move to try to pressure negotiators, Schumer warned that the Senate might need to work into the weekend or past Aug. 9, when they are scheduled to start their weeks-long summer break, in order to finish the agreement.

The group is also facing external hurdles. Republicans say the Biden White House has been throwing issues they viewed as closed back onto the table.

“It seems like the White House’s role has not been particularly constructive of late. I think there is a disconnect,” said Sen. John Thune (S.D.), the No. 2 Republican senator.

Portman added that the White House has “added some new challenges to the list.”

Democrats are worried that a Monday statement from former President Trump urging Republicans and Senate Minority Leader Mitch McConnell (R-Ky.) to reject any deal only complicates their chances.

“The former president spouting off doesn’t help,” Durbin told reporters.

Schumer publicly urged Republicans to ignore the former president, who maintains a strong grip on the party and is flirting with a White House run in 2024.

“Will our Republican colleagues follow the absurd demands of the disgraced former president and his media allies? … Republican Senators must ignore former President Trump if we’re ever going to make progress for the American people,” Schumer said. “He is rooting for our entire political system to fail.”