"Things are starting to move in the right direction. Conversations have all been positive,” said House Democratic Caucus Chair Hakeem Jeffries (D-N.Y.). “Everybody understands this has to happen."

“I do expect” a vote tonight, said House Majority Whip Jim Clyburn (D-S.C.).

A key part of Pelosi’s push on Thursday has been directed at the five centrist Democrats who have publicly declared they’d be unwilling to back the full bill until Congress’ nonpartisan scorekeepers can prove that the $1.75 trillion legislation will be fully paid for. Privately, even more centrists had aired the same grievance. Leaders chipped away at the holdouts — originally around a dozen — whose numbers have dwindled but are still numerous enough to block passage. Democrats can only afford to lose three votes without Republican support.

Democrats have been trying to close the gap on immigration as well. The three lawmakers who had staked their votes on immigration provisions met Thursday evening in Pelosi's office as they tried to amend the social spending package to include stronger protections for undocumented immigrants. One of the members, Rep. Lou Correa (D-Calif.), said: "Everything's on the table. We're trying to figure out how to get it off the table and into the bill."

As they left the meeting, Correa and the others announced they were drafting changes to the caucus' earlier language, which had included protections for undocumented immigrants but not a path to citizenship.

An earlier dispute with prescription drug pricing had been fixed, according to several lawmakers, after members like Rep. Scott Peters (D-Calif.), met with Democratic leaders. They emerged with tweaks to their legislation to change the number of years a drug has to be on the market before it can be subject to Medicare negotiations. Peters is now expected to support the legislation, according to multiple Democrats.

Meanwhile, Biden made some calls to reluctant Democrats to urge them to vote for the social spending bill, though he did not specifically advocate for a vote on Thursday and left the timing of a final vote up to Pelosi, according to a White House official. Rep. Abigail Spanberger (D-Va.) was among the lawmakers Biden called, according to a source familiar with the conversations.

Asked if she was hearing concerns from moderates, Pelosi told reporters as she left the floor: "We’re not hearing concerns. We’re doing our work. We’ll let you know."

Senior Democrats had hoped to make progress with those moderates thanks to the Joint Committee on Taxation, which released a slew of budgetary information earlier Thursday. The committee's incomplete estimate found at least $1.48 trillion of spending in the bill would be covered by the legislation's funding sources.

“It is essential that the legislation is fully paid for and reduces the debt,” Pelosi wrote in a letter to her members Thursday afternoon, where she stressed that newer provisions that weren’t included in that score — prescription drug pricing savings and IRS enforcement — are expected to raise another $650 billion.

But several centrists, who huddled to discuss the budgetary score later in the day, privately said they still needed more information before a floor vote on the social policy measure.

It’s not just the budgetary score: Many centrists have also refused to vote for a bill that won’t pass the Senate, with new provisions on immigration and paid leave provisions that face a grim future across the Capitol.

“It's hard to make a decision when you haven't seen the full text and there hasn't been a CBO score. But I'm hopeful,” said Rep. Kathleen Rice (D-N.Y.), who hasn’t committed to voting for the bill.

Regardless, Pelosi and her leadership team have been forceful in their efforts to bring the massive spending plan to the floor Thursday evening, with a Friday vote on the Senate-passed infrastructure bill, as she told members in a closed-door meeting Thursday morning. Those remarks came during a two-hour meeting of Democrats, where key committee chairs painstakingly outlined the provisions in the massive domestic policy bill as they readied members to vote for one of the largest bills in history.

"We’re going to pass both bills, but in order to do so, we have to have the votes for both bills,” Pelosi told reporters at her press conference after the meeting, declining to provide a firm schedule.

As they prepared for a last-ditch push Thursday, senior Democrats said they’d made key progress in several areas of contention, including immigration. But including immigration provisions at all has raised concerns from moderates, who have refused to pass a bill in the House that will just be gutted, or perhaps ignored entirely, by the Senate. Many moderates have insisted that the House should instead take up infrastructure on Thursday — which has already passed the Senate and been scored — while spending more time on the $1.75 trillion bill.

"There needs to be some level of understanding as to whether or not this bill, as written, can survive the Senate’s procedural process," said Rep. Stephanie Murphy (D-Fla.), a centrist leader.

For her, that includes immigration, which she said would be “selling immigrants a false hope” if any provisions are included that will simply be stripped out in the Senate.

Democrats' attempts to add immigration protections still face an enormous hurdle: the Senate parliamentarian. House Democrats say their colleagues in the upper-chamber have refused to take their newest compromise language to the upper chamber's rules arbiter, according to several people familiar with discussions. But those Senate Democrats have countered it’s because they don’t have a full score from the Congressional Budget Office.

"They haven't gotten a CBO score and without it we can't make the case," said Sen. Bob Mendendez (D-N.J.).

Months of infighting over Biden’s two giant bills has roused impatience to vote this week among the Democratic caucus — anxiety that was heightened after Democrats’ shellacking in Virginia and other states in Tuesday’s election.

After several failed attempts to clear one or both of Biden’s priorities, many Democrats said they were unwilling to leave the Capitol this week without achieving something.

Meanwhile, in the Senate, Democrats are still publicly projecting confidence they can take up the broader spending bill before Thanksgiving, but they also could go to a long-delayed defense policy bill if it’s not ready. The Senate leaves for recess on Thursday afternoon and returns Nov. 15.

“At some point, we’ve got to pass something. If Joe Manchin’s saying it’s gonna be weeks, let’s pass something on the House side,” said Rep. Ami Bera (D-Calif.)

Laura Barrón-López, Marianne LeVine and Burgess Everett contributed to this report.

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