The 38-year-old investment manager's "anti-woke" agenda focuses on recapturing the American dream from a country "lost" to "reverse racism", "climatism", "Covidism" and "gender ideology".
"This is our moment to start running to something, to our vision of what it means to be an American today," Vivek Ramaswamy says.
He's addressing the first TV debate of the 2024 presidential election.
The 38-year-old business investor is the youngest major Republican candidate in history - and he has no political experience.
He thinks Trump is "the best president of the 21st century" and - if he wins - has vowed to pardon him if he is convicted of federal crimes.
His "anti-woke" agenda focuses on recapturing the American dream from a country "lost" to "reverse racism", "climatism", "Covidism" and "gender ideology".
Let's take a closer look at who he is...
What matters to him?
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Mr Ramaswamy is a political novice. He considered running to be a senator in his native Ohio in 2022 but decided against it.
He announced his candidacy for the 2024 Republican nomination in February on Tucker Carlson Tonight. The right-wing, anti-immigrant, Trump-supporting commentator had his regular Fox News show cancelled in April with little explanation.
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Although he is an avid Trump supporter himself, having appeared outside the courthouse for two of the three cases lodged against the former president so far, Mr Ramaswamy has set about presenting himself as his successor.
He says he is prepared to go further than Mr Trump on several issues.
Instead of just building a wall along the US-Mexico border, for example, he said he would station soldiers at half-mile intervals along it.
He has promised to abolish the FBI, redeploying staff to what he believes are more effective agencies such as the US Marshals Service, so they can focus on issues like child sex trafficking.
In a huge departure from Western sentiment on Ukraine, he has said he would support a deal allowing Russia to retain what territory it has.
The Republican hopeful is soon to release a "comprehensive foreign policy vision" on Russia, China, Taiwan, India and other parts of Asia.
He has also drawn controversy for some of his comments, such as suggesting that federal agents may have been on planes involved in the 9/11 terrorist attacks.
What has he said?
Mr Ramaswamy has published two books - Woke Inc and Nation of Victims: Identity Politics, the Death of Merit, and the Path Back to Excellence.
In them he compares the "woke left" to "psychological slavery", claiming that like a "new secular religion" it "says your gender, race and sexual orientation determines who you are and what you can achieve in life".
"America is a systemically racist nation. That if you're black you're inherently disadvantaged. That if you're white you're inherently privileged," he adds.
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By contrast, he says America has become a place "full of victims" where "faith, patriotism and hard work have disappeared".
His campaign, he says will mean "a new movement to create a new American dream".
When he launched it on Instagram, he said: "We've celebrated our 'diversity' so much that we forgot all the ways we're really the same as Americans, bound by ideals that united a divided, headstrong group of people 250 years ago.
"I believe deep in my bones those ideals still exist. I'm running for president to revive them."
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What is his story and what is his net worth?
Mr Ramaswamy was born in Cincinnati, Ohio in 1985.
His parents are from Kerala, southern India. His father worked as an engineer and patent lawyer and his mother as a geriatric psychiatrist.
Although the family are Hindu, he attended Catholic school and credits his conservative Christian piano teacher there with informing many of his social views.
Having achieved top grades he studied biology at Harvard before attending Yale Law School.
While he was still studying he co-founded StudentBusinesses.com, which connected entrepreneurs to professional resources on the internet.
After graduating in 2007 he co-founded a similar venture called Campus Venture Network to help university students start their own businesses.
During the early years of career he worked in hedge funds, largely within biotech.
In 2014 he set up his own firm Roivant Sciences with the main aim of buying up drug patents that have been abandoned by the pharmaceutical industry.
A year later he pulled off one of the biggest IPOs (initial public offering) in the sector's history when he listed shares of its subsidiary company Axovant, which had previously bought the patent to an Alzheimer's drug from GlaxoSmithKline.
Despite having earned $315m (£248m) from the IPO - eventually the drug failed testing - an experience he has since said was "humiliating".
He stepped down as chief executive of Roivant in 2021, remaining chairman until this year but still retaining a 7% share in the company.
Last year he co-founded a new investment firm, Strive Asset Management.
It has been popular with right-wing backers and prides itself on being opposed to environment, societal and corporate governance (ESG). The system, increasingly adopted by top firms, encourages them to make responsible investment decisions for good causes.
Now he claims to have widespread support from young voters and new donors. He says around 40% of his 700,000 financial backers have offered small contributions and are donating to a political candidate for the first time.
Forbes reported his net worth at $630m (£495m) and so far he has spent $15m (£11.8m) of it on his campaign.
