He's an environmentalist and conspiracy theorist, an anti-establishment figure from one of America's most storied political families, a virile 70-year-old with a host of health issues.
It can be hard to get a handle on Robert F Kennedy Jr, the nephew of former president John F Kennedy, but one thing's for sure: his bid for the White House can't be easily dismissed.
The independent candidate has fallen short of qualifying for this week's presidential debate, but his polling numbers — up to around 15 per cent — suggest his candidacy could be a deciding factor in who takes the Oval Office in 2024.
That's because the winner of the expected Biden–Trump rematch could be determined by a relatively small number of votes in a handful of swing states. If RFK Jr siphons significantly more support from one of the main candidates than the other, it could make all the difference.
A famous name doesn't get you on the ballot
As America endures the year's first heatwave, Colin McEvers is sweating in his shirt and tie in downtown Annapolis, Maryland, trying to recruit passers-by to support RFK Jr's presidential bid.
"Hi guys, how are you doing today?" the towering teenager says, as all 6 foot, 10 inches of him strides towards a couple in their early 40s.
"Sorry to bother you. My name's Colin.
"I'm working for the RFK Jr campaign. We're just trying to get some signatures to get an independent on the ballot for Maryland... as another option besides Biden and Trump, basically."
Third-party candidates are not guaranteed to get their names on ballots in US elections. The requirements vary from state to state. Here in Maryland, RFK Jr needs 10,000 verified names on a petition.
McEvers, the state campaign co-ordinator, says he's personally collected more than 3,000.
With polls showing a majority of voters have unfavourable views of both Joe Biden and Donald Trump, the case for a third option is hitting home.
"Trump and Biden are both often off the rails," says Karl Klinghard, who's visiting from Tennessee and says he'll "probably" vote for RFK Jr in this November's election.
"I think RFK couldn't do any harm," he says.
"I like his environmental aspect, and I think he's got a lot to offer, you know just from his background and private industry and all those things."
A life marked by tragedy and conspiracy
RFK Jr was nine years old when his uncle, then-president John F Kennedy, was assassinated in 1963.
Five years later, Robert F Kennedy — JFK's brother and the current candidate's father — was also shot dead while he was seeking the Democratic presidential nomination.
RFK Jr, one of the late Bobby Kennedy's 11 children, has long espoused the view that the death of his uncle was orchestrated by the CIA.
He's also called for a new investigation into the murder of his father, arguing the evidence suggests the man serving a life sentence for the killing, Sirhan Sirhan, did not fire the fatal shots.
Perhaps these experiences helped shape RFK Jr's deep distrust of government, institutions and the media, a worldview that has seen him embrace vaccine conspiracy theories.
He's been a vocal advocate of the now-debunked theory that vaccines in children are linked to autism. During the pandemic, he suggested COVID may have been engineered to target certain ethnic groups, and appeared to back a theory that Bill Gates was using the vaccine to control people via microchip.
"What was yesterday's conspiracy theory is today's truth," says Josh Mazer, Maryland Team Kennedy campaign co-ordinator.
"He's simply the most intelligent person in any room I've ever walked into."
In recent campaign appearances, RFK Jr has appeared to tone down his vaccine rhetoric, but still rails against COVID public health measures. He described them as "the greatest restriction on individual liberties this country has ever known" during a recent speech at the Libertarian Party convention in Washington DC.
The speech also touched on one of RFK Jr's core policy proposals: slashing military funding and getting out of foreign wars.
"We have forfeited our moral authority because we have supported dictators and corrupt regimes and subverted democracy around the globe," he told the crowd.
Some of the biggest cheers came when he said that, on his first day in office, he would drop all charges against Julian Assange and pardon Edward Snowden.
"Free Assange, free Assange," audience members chanted.
As news broke on Monday, local time, that Mr Assange had reached a plea deal with US authorities, RFK Jr suggested that a monument be built to the Australian to educate the American public about the importance of free speech.
Describing Mr Assange as a “generational hero”, RFK Jr lamented the terms of the deal, which he said meant the US had succeeded in criminalising journalism.
While the Libertarians didn't vote him in as their 2024 candidate, he had plenty of fans in the room.
"I like the fact that he's not a politician," said Nancy Lou Little, a veterinarian who shares his scepticism about vaccines, America's health regulation bodies and big pharma.
"When I first heard him interviewed, I started crying because he was talking about our health problems. And I've been waiting 35 years for somebody to talk about those."
Spoiler alert for Biden and Trump
RFK Jr began his bid as a Democratic candidate, challenging Joe Biden for the nomination.
Last October, he announced he was running as an independent.
His "America First" tendencies and distrust of big government potentially appeals to Republican voters.
Yet his credentials as an environmental lawyer who helped clean up the Hudson River in New York, and his rejection of a ban on TikTok, could see win him support from younger, more left-leaning voters.
That's the thing with RFK Jr — you can really choose your own adventure.
"I'm not sure anyone knows where he stands because he is all over the place ideologically," says Bernard Tamas, a professor of political science at Valdosta State University in Georgia.
"A big part of his appeal is the fact that Americans are very disenchanted with the political system right now and with both candidates."
Colin McEvers, the campaigner in Maryland, likes what he sees of the candidate's plans to make first home loans more affordable by guaranteeing government-backed mortgage interest rates.
"I want to own a home in the future, I want to build a family, and it's very hard for people of my age range to do that."
The famous last name and clever use of social media — not to mention his wealthy running mate, Silicon Valley entrepreneur and philanthropist Nicole Shanahan —are all helping RFK Jr outpoll the other third-party candidates.
Recent polling also suggests his campaign is attracting young people and Latinos in particular, and that's a worry for Democrats who have traditionally done well with those voter groups.
But Dr Tamas says third-party candidates have historically seen their support wane as election day nears.
"Most people return to want to vote for one of the two major party candidates," he says.
"You're not likely to see progressive voters sticking, or large percentages of them sticking, with third-party candidates when they're afraid of Donald Trump going back into the White House."
While Republicans initially seemed less worried about RFK Jr's potential, their position has started to sharpen.
In a recent social media post, Donald Trump referred to him simply as "Junior" and suggested he was a "Democrat plant".
Dr Tamas says he's starting to see signs RFK Jr could be more of a threat to Trump than Biden.
"The fear, I think, is that he is going to take votes from what we call the 'Never Trumpers', the moderates that don't like Biden but don't like Trump either."
Family rifts play out on social media
Jack Schlossberg was a vocal opponent of his cousin's candidacy from the outset.
"He's trading in on Camelot, celebrity, conspiracy theories and conflict for personal gain and fame... his candidacy is an embarrassment," JFK's grandson said in a video posted last year.
More recently, the posts by the 31-year-old son of Australia's US Ambassador Caroline Kennedy have taken on a more colourful twist.
In a series of videos, Schlossberg adopted various fake personas — including a southerner named Wade, a Russian named Vlad and a New Yorker named Joshua — to describe RFK Jr as a liar who was pumped full of testosterone and who was playing into Russia's hands.
Other prominent members of the Kennedy clan have also come out against RFK Jr, describing his candidacy as perilous and saddening.
The family, as close to Democratic royalty as it gets, was not happy that a campaign ad played at the Superbowl traded on their name.
The Kennedys' connection to the current Democratic president is also founded in their shared Irish Catholic roots.
Family members posed at the White House with the president on St Patrick's Day and more than a dozen of them, including five of RFK Jr's siblings, endorsed Biden at a campaign event the following month.
So what's this about a brain worm?
At 70, RFK Jr is a relatively young man compared to Biden, 81, and Trump, 78.
He makes a virtue of his physical prowess.
Internet users briefly lost their minds over videos of him working out shirtless.
Fox News swooned about his "sheer masculinity", CNN said there was "nothing junior about RFK Jr's pecs".
But RFK Jr also has some significant health challenges.
His voice is gravelly and strained — a result, he says, of a neurological condition known as spasmodic dysphonia.
"I think it makes it problematical for people to listen to me," he told News Nation.
"I cannot listen to myself on TV, I will never listen to this broadcast."
And then there's the worm.
New York Times reporting revealed that RFK Jr claims to have suffered cognitive issues starting around 2010, including memory loss and brain fog, due to a parasite in his brain.
During his divorce proceedings, he said that a doctor had told him his problems could be "caused by a worm that got into my brain and ate a portion of it and then died".
Shortly after the reports surfaced, RFK Jr leaned in, joking about eating more brain worms.
He hasn't produced medical records on said parasite, but his campaign says he has now recovered.
His connection with the natural world goes far beyond worms.
He has several dogs and is a bird enthusiast who once kept an emu. And he recently introduced his followers to the two ravens who "join him" for meditations on his balcony every day, and who he says he's "taming".
It might seem out there, but perhaps the kind of voter attracted to RFK Jr sees it as part and parcel of his unconventional appeal.
There's certainly no sign that news of the ravens or the brain worm have damaged his run.
While he didn't make it into the first presidential debate, under rules based on ballot access and poll numbers, it's possible he could qualify for the second one.
That kind of airtime is something neither the Biden or Trump campaign is likely to welcome in a contest predicted to come down to the wire.
"I think both candidates, both campaigns should be concerned about RFK," says Dr Tamas.
"Because this election is going to be extremely, extremely close."
