When lawmakers arrived on Capitol Hill last Monday, House GOP leaders’ plans to sync up with the Senate on sweeping legislation to advance President Donald Trump’s agenda seemed an all-but-impossible task.

House fiscal hawks were furious with Senate Republicans for passing an amended version of the former’s budget framework, one that called for a significantly lower amount of mandatory spending cuts than the House’s initial plan.

By late Thursday morning, House Speaker Mike Johnson, R-La., was celebrating victory in front of reporters after a narrow 216-to-214 vote.

“I told you not to doubt us,” a triumphant Johnson told the media. “We’re really grateful to have had the big victory on the floor just now. It was a big one, a very important one.”

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The hard-fought win came after long hours and late nights as House Republican leaders — and leaders in the Senate GOP as well — worked to persuade holdouts, while Trump and his aides worked those same critics from the sidelines.

White House aides were at House Republicans’ weekly conference meeting on Tuesday, a rare sight but not unexpected, given the importance of the coming vote.

But GOP lawmakers filed out of that meeting doubting whether Trump’s influence could help this time, after he played a key role in helping shepherd earlier critical bills across the finish line this year.

“I don’t see it happening,” a House Republican told Fox News Digital when asked whether Trump would be enough to sway critics.

Nevertheless, a select group of those holdouts were summoned to the White House alongside House GOP leaders on Wednesday afternoon, hours before the expected vote.

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Fox News Digital was told that Trump commanded the room for roughly 20 to 30 minutes, and told House conservatives he agreed with them on the need to significantly slash government spending.

Trump also communicated to holdouts that Senate leaders felt the same, but, like the House, were working on their own tight margins, Fox News Digital was told.

The president, meanwhile, has been concerned in particular with the looming debt limit deadline, Fox News Digital was told.

It’s one of the issues that Republicans are looking to tackle via the budget reconciliation process. By lowering the Senate’s passage threshold from 60 votes to 51, it allows the party controlling the House, Senate and White House to enact broad policy changes via one or two broad pieces of legislation.

In this case, Republicans are looking for some added funds for border security and defense and to raise the debt ceiling — while paring back spending on the former Biden administration’s green energy policies and in other sections of the federal government, likely including entitlement programs.

GOP lawmakers are also looking to extend Trump’s 2017 Tax Cuts and Jobs Act, the provisions of which expire at the end of this year. They will also need new funding for Trump’s efforts to eliminate taxes on tipped and overtime wages.

But first, Republicans wanted the House and Senate to pass identical frameworks setting the stage for filling those frameworks with actual legislative policy.

Whereas the House version calls for at least $1.5 trillion in spending cuts, the Senate mandated a floor of $4 billion — a wide gap to bridge.

The Wednesday-afternoon White House meeting did sway some holdouts, but far from enough. 

Senate Majority Leader John Thune, R-S.D., also met with House GOP critics of the bill for more than an hour on Wednesday evening ahead of the planned vote.

“He couldn’t have been more cordial and understanding in talking to us about what we needed to know. And honestly, he had some of the same concerns that we did,” Rep. Tim Burchett, R-Tenn., told Fox News Digital.

“You know, he’s got to get it over the finish line, and he had to make certain commitments. But he committed to us to work with us.”

Ultimately, however, plans to advance the measure that evening were hastily scrapped as an unrelated vote was held open for over an hour, leading to confusion and frustration on the House floor.

“He looked like he was in no better spot than he was at the beginning,” one House Republican said of that night.

Trump was not called to address the group during that huddle with holdouts, two sources in the room told Fox News Digital. 

However, the president did have individual conversations with some holdouts on Wednesday and Thursday, one person said.

The Wednesday night failure gave way to a late night of negotiations involving both holdouts and House GOP leaders.

Two House GOP leadership aides told Fox News Digital that Johnson had huddled with Majority Leader Steve Scalise, R-La., and House GOP Conference Chairwoman Lisa McClain, R-Mich., until late Wednesday to figure out a path forward.

When they emerged shortly before midnight, they had settled on a plan — a televised promise by Johnson and Thune to put both leaders on the record committing to deep spending cuts.

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“I’m happy to tell you that this morning, I believe we have the votes to finally adopt the budget resolution so we can move forward on President Trump’s very important agenda for the American people,” Johnson said.

Thune added, “We are aligned with the House in terms of what their budget resolution outlined in terms of savings. The speaker has talked about $1.5 trillion. We have a lot of United States senators who believe in that as a minimum.”

A senior Senate GOP aide argued to Fox News Digital, “Absent Thune’s intervention, Mike Johnson would not have gotten this resolution through the House.”

But the speaker was also putting in his own long hours with holdouts.

The office of Rep. Ralph Norman, R-S.C., who ultimately voted to advance the framework, told Fox News Digital that critics were sent a memo by Johnson early on Thursday, assuring them that he was committed to deep spending cuts.

“The Senate amendment to H. Con. Res. 14 preserves untouched language from the original House-passed resolution, including the reconciliation instructions to House committees and Section 4001 — Adjustment for spending cuts of at least $2 trillion,” the memo said.

It referred to a measure in the House-passed framework that suggested funding toward tax cuts would be reduced by a corresponding amount if final spending cuts did not equal $2 trillion.

“This language reflects a critical principle — that deficit-increasing provisions of the final reconciliation bill are accompanied by concomitant spending cuts,” it said.

Then, as the vote was called around 10:30 a.m. on Thursday morning, a final huddle between holdouts and leaders sealed the Republicans’ victory.

“At some point, it was heated. And then the speaker’s leadership team [House Majority Whip Tom Emmer, R-Minn.] made sure we were clarified on some issues which are very important to some of the members,” Burchett said.

“And then Steve Scalise, really batting cleanup, and he came in with the final with the final conclusion, which everybody agreed to pretty much. And then the speaker closed the deal.”

Burchett said he believed that Johnson had spoken to Trump separately at some point during that huddle.

A senior House GOP aide said McClain was also present for that meeting.

Republicans clinched the win minutes after 11 a.m. on Thursday, with the GOP side of the House chamber erupting in applause.

House Freedom Caucus Chairman Andy Harris, R-Md., who helped lead the opposition, told reporters after the vote, “We made tremendous progress over the last two days in making certain that whatever we do on reconciliation, we don’t increase this country’s budget deficit.”

“We take the Moody report from two weeks ago pretty seriously, that you can’t have unpaid-for tax cuts, and we made progress in making, getting assurances both from the Senate and the House leadership that that’s not going to occur,” Harris said.