One of the first people JD Vance called before deciding to jump into politics was Charlie Kirk.

"[Kirk] introduced me to some of the people who would run my [Senate] campaign and also to Donald Trump Jr," the vice-president wrote in a powerful tribute he penned hours after Kirk's death.

"Don took a call from me because Charlie asked him."

Three years after that winning Senate run, when the elder Donald Trump was pondering his choice of presidential running mate, Kirk argued the case for Vance "in public and private", Vance wrote.

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By then, Kirk was already a fixture in Trump's orbit, courting donors and discussing strategies at Trump's Mar-a-Lago estate in Florida and hosting Turning Point USA summits hosted by local Republicans.

He never ran for office or held an official government position, but Kirk rose from being an unknown activist from the suburbs of Chicago to standard bearer of Donald Trump's Maga movement.

Kirk was President Trump's bridge to young Republicans, and Trump credited him and his organisation with his victory in 2024.

He was also a close personal friend of the Trump family, a key White House adviser, a hero to many young Republicans and a foil for the party's opponents.

A meteoric rise to MAGA star

Born in a suburb of Chicago in 1993, Kirk got started early in conservative politics, first penning an essay for right-wing Breitbart News at the age of 18, accusing schools of spreading "propaganda" and "indoctrination".

He caught the eye of Bill Montgomery, a retired businessman and Tea Party activist more than 50 years his senior, who took Kirk under his wing.

In 2012 – around the midpoint of Barack Obama's presidency – the pair founded Turning Point USA (TPUSA), a group which focused on conservative activism on college campuses, spreading rapidly along with Kirk's social media following.

The group tapped into online media and spread a slickly packaged style of conservatism to young people. It won him a speaking place, aged 22, at the 2016 Republican National Convention.

At the time, Kirk - who had worked with more conventional Republican candidates in the past - admitted to a Wired magazine that he "was not the world's biggest Donald Trump fan".

But from that moment on he quickly became one of Trump's biggest backers, steadfastly tracking the Maga agenda and disagreeing only on rare occasions.

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Following Kirk's death, Jared Kushner - the president's son in-law - wrote on X that he "played a significant role in helping President Trump's 2016 campaign, building and fostering the Maga movement", adding that he told established political organisations that "he comes with big ideas, is easy to work with and always overdelivers."

Lawrence Muir, a former official in Trump's first administration, said that Kirk's influence was key early on in Trump's first term, and that TPUSA "was the main recruitment vehicle for younger people."

But perhaps his more far-reaching impact, Mr Muir said, was in giving other conservatives an understanding of social media and how to reach young people.

"What [Kirk] really did was give a launching pad to those who weren't as interested in becoming bureaucratic functionaries, but were in going out and building winning coalitions," he said.

Hard-right Trump loyalist

Kirk's political views drifted rightward over time. He was against gay marriage and abortion, argued for Christian nationalism and was highly critical of Islam, and famously said that gun deaths were "worth it" for the right to own firearms. He was also an opponent of diversity programmes and spread falsehoods about topics such as Covid vaccines and voting fraud.

Above all, he was loyal to Trump.

At the end of Trump's first term, with the president pushing false allegations of election fraud, Kirk bragged about sending 80 buses of supporters to Washington just in time for the rally which devolved into the Jan 6 riot at the US Capitol.

Kirk was hauled in front of a Congressional committee investigating the riot and declined to say much of anything, instead invoking his constitutional right not to incriminate himself.

But by July 2024 he had tempered his views, telling the BBC that he believed it existed but only "on the edges". Instead, he said and his group were laser focused - like the Trump campaign - on maximising early voting methods that they had previously shunned as illegitimate and ripe for fraud.

Kirk poured millions of TPUSA dollars and thousands of volunteers into get-out-the-vote efforts in swing states during last year's election, and his strategy appears to have worked.

The organisation's "ground game" was crucial, analysts say, helping make up for the formal Trump campaign's struggles reaching infrequent voters, or those untouched by traditional outreach.

Although Democrat Kamala Harris won the youth vote overall, it was by a far smaller margin than that of Joe Biden's 2020 victory.

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Trump himself gave Kirk credit at TPUSA's annual AmericaFest conference in December, just a few weeks after his election victory.

"I want to express my tremendous gratitude to Charlie Kirk. He's really an amazing guy, amazing guy and his whole staff for their relentless efforts to achieve this very historic victory," Trump said.

The gathering was triumphant, bombastic and slickly produced, with huge video screens - a demonstration of TPUSA's deep pockets. The group has now spread to 3,500 high schools and colleges and brought in more than $85m (£62m) last year, according to investigative journalism outlet ProPublica.

It also showed off Kirk's ability to bring together disparate wings of the Make America Great Again movement - members of Congress, dark arts strategists like Roger Stone and conspiracy-obsessed social media influencers.

Donald Trump Jr (l) with JD Vance (c) and Charlie Kirk (r) on stage during the Turning Point USA Inaugural Eve Ball in Washington, DC in January

Ever closer to White House power

Kirk's influence arguably grew even more during Trump's second term. Just two days before Trump took office, the pair played golf together in Mar-a-Lago.

His relationships with Trump and the rest of the family even gave him sway over government posts - Kirk was reportedly involved in vetting administration appointees earlier this year.

In his tribute, Vance wrote: "He didn't just help us win in 2024, he helped us staff the entire government."

And while his social media and podcast output continued at pace, along with campus tours and other speaking commitments, he continued to hew to Trump's agenda.

After criticising the Justice Department for dragging its feet on releasing files related to the sex offender Jeffrey Epstein, he took a phone call with Trump. Shortly thereafter, Kirk declared that he was "done talking about Epstein".

News of his killing hit the White House hard, starting with the startled gasps of young staffers who saw news of the shooting while scrolling on their phones.

"Oh my God," one young woman was heard saying, before scurrying down a hallway to tell others. "Charlie Kirk has been shot!"

Some staff were wiping away tears. President Trump received updates and fielded phone calls from the Oval Office before ultimately taking to Truth Social to publicly confirm his death and later delivering a video address on his murder and ordering flags across the country to fly at half-staff.

"Charlie was very much a part of this family, and maybe the highest-profile Maga person outside of those that are working here," Chief-of-Staff Susie Wiles told CNN. "I think it shook everybody to their core."

Donald Trump Jr posted his own message saying that Kirk "wasn't just a friend, he was like a little brother to me.

Dr Matthew Dallek, a professor at George Washington University and expert on modern conservatism, said that the close personal ties between Kirk and the Trump family were "really important" to the TPUSA founder's broader influence.

"Trump prizes loyalty, above maybe anything else," he said. "And if Don Jr is saying he was like a brother to him, that suggests just how great a supporter Kirk was. They viewed him as an absolutely critical ally and advisor.

"There was a kindred spirit there, and they did not have to worry about him bolting from the movement. He was loyal."(CNN)

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