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(ATKINSON, N.H.) — When Vivek Ramaswamy took the stage in Atkinson, New Hampshire, on Tuesday just one day after ending his presidential campaign, he gave a passionate speech.

It was the same speech, in fact, Ramaswamy had given on the trail multiple times when pitching himself to voters, but with one exception: He replaced the references to himself with references to Donald Trump.

In less than 24 hours, Ramaswamy, a biotech businessman and conservative commentator who campaigned as the most Trump-friendly, “America first” alternative in the GOP field, dropped out of the 2024 race and endorsed his former opponent.

In New Hampshire, he appeared alongside the man who — as recently as Saturday — had accused him of “deceitful campaign tricks” and not being “MAGA.”

But there was little bad blood to be seen between them on Tuesday.

“We are in the middle of a war in this country,” Ramaswamy said, portraying a country divided between “those of us who love the United States of America and a fringe minority who hates this country and what we stand for.”

“And right now we need a commander in chief who will lead us to victory,” he said.

The former president soon returned the favor.

“I’ve been a friend of his even though we were competing against each other,” Trump said. “But I was a friend of his and we got along and … I kept saying, ‘Why is he running? He keeps calling me a great president.’ But he’s a fantastic guy, a very smart guy. He’s got some tremendous ideas.”

The end of Ramaswamy’s campaign marked the beginning of his next chapter: as a vocal Trump campaign surrogate.

“He’s going to be working with us for a long time,” Trump said Tuesday after some in the crowd chanted “VP, VP, VP.”

For a while, at least, it looked like Ramaswamy was gaining some traction with Republican voters in Iowa and nationwide. His campaign, while initially little watched, helped him build a larger and larger profile with conservatives.

He saw his polling peak of about 11% on Aug. 23, which was then higher than the support for Chris Christie, Nikki Haley, Mike Pence and others.

That was also the day of the first primary debate when Ramaswamy stood out for standing by Trump, keeping his hand raised longer than any other candidates on stage when asked if he would still back Trump as the Republican nominee were the former president to be convicted of the charges he faces. (Trump has pleaded not guilty and denies all wrongdoing.)

Ramaswamy’s commitment became a major part of his pitch to voters, even pledging to keep Trump on as an adviser, if not his vice president, if he reached the White House.

But, eventually, there was a shift. While still generally complimentary of Trump, Ramaswamy began to compare Trump to a “wounded” soldier, saying, “If you want to save Trump,” Iowans should vote for him instead so as not to play into “the deep state’s trap” of, he claimed conspiratorially, narrowing the race to eliminate Trump and prop up Haley instead.

What had seemed to be an unusually amicable relationship between the competitors hit a rough patch just two days before the Iowa caucuses, after the Ramaswamy campaign handed out shirts reading “Save Trump, Vote Vivek.”

Trump went after him for that, posting on social media that the move was “very sly, but a vote for Vivek is a vote for the ‘other side’ — don’t get duped by this. Vote for ‘TRUMP,’ don’t waste your vote!”

The rift was short lived though, as Ramaswamy quickly rallied behind Trump after Trump’s big win in the Iowa caucuses, calling him in congratulations on Monday night.

“I expect to join him tomorrow in New Hampshire and I think that I will expect to join him on the campaign trail after that as well, because I think it’s important that he becomes the next president of the United States,” Ramaswamy told ABC News.

It wasn’t the outcome Ramaswamy himself had sought, he acknowledged. But by then, his own momentum in the polls had faded, with 538’s surveys of likely voters who watched each primary debate showing he drew divisive reactions.

According to 538 averages, Ramaswamy was at just 6.4% in Iowa by caucus day.

Still, his campaign boasted of a “major upset,” and his Iowa ground game was not lacking.

He held more than 300 events in the state over his nearly 11-month campaign, even relocating to Des Moines, and pulled a large showing at many events through the end of his bid.

He had insisted to voters up to the day before the caucuses that he’d stay in through the general election regardless of his performance in Iowa.

On Monday night, however, he told supporters something else.

“We looked at it every which way and I think it is true that we did not achieve the surprise that we wanted to deliver tonight,” he said in a speech as the results were coming in that showed him in a distant fourth place.

He suspended his campaign after meeting with some of his staff at a caucus celebration party, later telling ABC News the decision to drop was one made by him and his wife, Dr. Apoorva Ramaswamy.

Vivek Ramaswamy now says he’s going to do “everything” he can to support Trump in the race.

“If it’s not going to be me — and it’s not, as of tonight that’s clear — I think that Trump should be the next president of the United States and I’m going to do everything that I can to make it so,” he said Monday of his choice to head to New Hampshire.

When previously asked if he would consider a role as Trump’s vice president, Ramaswamy would usually say something to the effect of “I love the man, but I can only lead from the front,” as he told a voter earlier on Monday.

But hours later, when asked by ABC News, he said he “would evaluate whatever is best for the future of this country.”

He did not rule out a run in 2028 either, telling ABC News, “I think that this movement is just getting started.”

But, he added, “Who’s going to be the best vehicle to advance that agenda forward? Right now, that’s Donald Trump and he has my full support for that reason. But ‘America first’ doesn’t end in 2028. It doesn’t end in 2032. It goes for another 250 years, and that’s what I think is ahead for this country.”

ABC News’ Lalee Ibssa and Soo Rin Kim contributed to this report.

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