EXCLUSIVE: There are few people in the United States who have more significantly shaped the course of American history over the last two years, while remaining as little-known as James Braid.

Millions of Americans across the country may not be familiar with the name, but in Washington, D.C., Braid is hard to miss both literally and figuratively. At 6 feet, 6 inches tall, he cast a tall shadow during his days at the White House and on Capitol Hill pushing President Donald Trump’s legislative agenda.

And that shadow has been responsible for helping push numerous legislative successes for Trump over the finish line, from rolling back Biden-era policies to passing Trump’s signature tax policy bill, until Tuesday — which marked Braid’s last day as director of the Office of Legislative Affairs. The "stock-in-trade" of the job, he told Fox News Digital in a rare interview, "is cautious optimism in the face of all odds." From the outside, being Trump’s whisperer on Capitol Hill does not look like an easy job, particularly when the president is known to personally call out lawmakers who oppose his agenda.

Recently, for example, he publicized the personal phone number of Sen. Tom Cotton, R-Ark., over his opposition to a bill making daylight saving time permanent.

TRUMP DROPS REPUBLICAN SENATOR'S PHONE NUMBER IN SOCIAL POST OVER FURY ON STALLED BILL But Braid insisted that Trump’s people skills ultimately meant those dust-ups came out of the wash and lauded "his extraordinary capacity to have a tough conversation one day and play a round of golf the next."

"There's always a give-and-take in any relationship with a legislator, and sometimes there's a give as a result of, you know, tension," Braid said. "But you know … one errant Truth [Social post], or one critical Truth, does not a relationship make." But some Republicans’ relationships with the president never seemed to recover, like in the case of Sen. Mitch McConnell, R-Ky., who has no love lost with Trump. Braid said the key to working with people was always being straightforward about what the White House wants.

"We've been able to be honest brokers and deliver for a lot of these members in different ways," he said. But Trump’s presence still looms large in Congress whether he’s there in person or not.

A senior administration official familiar with Braid’s work told Fox News Digital that ultimately, "No one speaks for President Trump except for President Trump." The official said Trump is known to be "hands-on at every critical legislative juncture" that pushes his agenda forward. And Braid revealed that he keeps tabs on certain votes, as well.

"He always wants to know how people are voting after every major vote. He knows where people are," Braid said, adding that Trump "ultimately knows that Republicans in Congress overwhelmingly vote with him." But Braid admitted he has faced long odds over his last two years, particularly with the vast tax-and-policy package nicknamed the Big, Beautiful Bill.

MILLIONS TAP TRUMP TAX CUTS THIS FILING SEASON AS REFUNDS TOP $3,400 He recalled sitting in his office one day, "I looked at the quad on the TV, and every single chyron is some variation of ‘GOP megabill in trouble.’And yeah, I mean, there's certainly, at every moment, it was tenuous. At every moment, the thread was fraying." One specific scenario he recalled took place at Sterling Golf Club in Virginia, where he, Trump, Office of Management and Budget (OMB) Director Russell Vought and then-deputy chief of staff James Blair were meeting with Senate Republican holdouts on the legislation.

GOP FISCAL HAWK SOUNDS ALARM ON 'OUT OF CONTROL' FEDERAL SPENDING, SAYING 'BOTH PARTIES HAVE FAILED US' "We're sitting there with [Sen. Rand Paul, R-Ky.], [Sen. Ron Johnson, R-Wis.], [Sen. Rick Scott, R-Fla.], me, Blair, Russ and the president, and they're bringing out these heaps of food," Braid recalled. "I think there's something like four pizzas on the table and maybe 22 hot dogs for five guys, none of them were eating.

And it's just, I mean, we, I think we argued about the administration's overall funding strategy for two hours as the afternoon wore on."

Ultimately, however, the bill passed the House and Senate — for which Braid credited both administration officials and congressional leaders.

"The level of commitment that was there and present from the leadership across the Republican Party to get this thing done, basically willed it into being," he said. He referenced the day Trump signed the bill when asked about his best day on the job over the last two years: "I would say July 4th in the White House with my son and the speaker of the House in the summer sunshine, watching the president sign the most significant piece of Republican domestic policy legislation." Top congressional leaders hailed Braid as a critical champion of the GOP agenda.

"James is a total pro and one of House Republicans’ greatest teammates," House Majority Whip Tom Emmer, R-Minn., said. "He took the time to get to know our members and master the unique dynamics of the House Republican Conference." Senate Majority Leader John Thune, R-S.D., called Braid a "tremendous partner" for his conference.

"I’m grateful for his dedicated service to our country, and I wish him and his family all the best with their next chapter," Thune said. Vought called Braid a "lion for the president in delivering his agenda on the Hill."

And Vice President JD Vance, who hired Braid as his legislative director before both ascended to the White House, told Fox News Digital that he is "incredibly brilliant, effective and a hard worker without compare." "He has been with me since the start of my Senate term, where he was with me for every fight and brought his talents to the president’s second term, where he has played a central role in every single policy effort since," Vance said.

Now that he is departing, the senior administration official who spoke with Fox News Digital said they expect Braid to find work outside the government after years of grinding on Capitol Hill and the White House.

As for Braid, he said of his next move, "It's hard for me to even think about not doing this job, but at the end of the day, I know [Katie Bailey is] going to do great … but yeah, I'll take a little time and try to figure out what's next." Bailey, Braid's former deputy director of the Office of Legislative Affairs, is now taking over the job. He summed up his advice to his successor in two bullet points.

"Number one, you have to be ruthless in what you're focused on and tune out the distractions to get the issue of the day over the line and onto the president's desk," he said. "Number two, invariably, the situation feels pretty grave, but usually we muddle through, and to remain optimistic."