He's a crazy-haired populist who was born in New York and nearly split his conservative party, but appears to have come out on top.

He's wealthy, but appeals to working-class voters. He's tough on immigration, and keen to point out President Obama's Kenyan heritage. Lots of people call him by his first name only. He once starred on TV.

He's not Donald Trump.

He's Boris Johnson, who was the mayor of London until he stepped down last month. Now he could become the United Kingdom's next prime minister.

Johnson was one of the leaders of the "Brexit" campaign, and he could be one of the big winners now that Britons have voted in favor of leaving the European Union.

"I believe the British people have spoken up for democracy, in Britain and across Europe," Johnson said at a news conference Friday. "I think we can be very proud of the result."

Prime Minister David Cameron, who campaigned hard for Britain to remain in the EU, announced Friday that he will step down by October. That immediately set off the race for a successor.

Johnson said he was saddened by Cameron's decision to resign, but called his former college buddy "brave and principled ... one of the most extraordinary politicians of our age."

Both are members of the Conservative Party, which won an outright majority in Parliament last year and will choose the next prime minister.

Over the next three months, Conservatives will pick two candidates, and then the party's members will decide which one will be the next leader of their party, and thus the country.

Inspires Strong Feelings

While Johnson is seen by many as the favorite, he has his detractors. An angry crowd booed him Friday morning as he left his north London home.

He's a former journalist who was known for his stories from Brussels in the 1980s and '90s that were skeptical of European integration. He worked then for the Times of London and still writes a column for The Telegraph.

That's where he announced his support for Brexit in February, though he admitted he wrote two versions of the column — one in favor of leaving Europe and the other in favor of staying — and chose pro-Brexit at the last minute.

Johnson is also a historian and author. He was born in the U.S. to British parents, and therefore has dual U.K.-U.S. citizenship, though he's said he intends to give up his U.S. passport after being slapped with a rather large U.S. tax bill recently.

He also has an outsized personality, and a reputation for what the British call buffoonery.

"He's got a bit of a caricature look," London commuter Karen Gilchrist said, referring to the ex-mayor's signature mop of white-blonde hair. "He does seem to be engaged with his city. But also, he does have a habit of putting his foot in it," she says with a laugh. "A little bit akin to Donald Trump, probably."

On a recent day, Gilchrist was renting one of the so-called "Boris bikes" at a municipal bike kiosk on the edge of the River Thames. London's self-service, public bike-share scheme is nicknamed for Johnson, a bicycle enthusiast who presided over its 2010 launch, though it was in the works before he took office.

Johnson served two terms as London mayor, and was succeeded by Sadiq Khan last month.

While still mayor, Johnson took issue with Obama, when the U.S. president visited London this past spring and urged Britons to vote to stay in the EU.

"I'm a big fan of Barack Obama, but clearly we have a disagreement," Johnson told reporters. "And I do think it's perverse that we're being urged by the United States to embroil ourselves ever more deeply in a system ... when the United States wouldn't dream of subjugating itself."

Johnson accused Obama of meddling, and wrote in a tabloid newspaper column that Obama dislikes Britain because of his Kenyan ancestry.

Obama is widely beloved in Britain, and within days, Johnson's E.U. exit campaign took a hit in the polls. But that trend, in the end, was short-lived.

Future Ambitions

Johnson is one of the most-liked politicians in Britain.

"He makes us laugh," said Mark Lenaghan, a construction worker on a cigarette break in central London. "Well, [he's] a bit of a clown, really."

A clown who's willing to make a fool of himself to promote his city, something Lenaghan says he finds endearing.

During the 2012 London Olympics, Johnson got stuck on a zip line over East London. He was left dangling 20 feet off the ground in a hardhat and harness, waving a Union Jack in each hand.

"Get me a ladder!" he joked to passersby below, waving his flags and smiling for photos.

Despite such antics — or perhaps because of them — Johnson remains an extremely popular figure in London. There's always been speculation about his political aspirations, about which he once famously said: "My chances of being prime minister are about as good as the chances of finding Elvis on Mars."

But many believe now might be the time. The challenge for Johnson, said his biographer Andrew Gimson, would be to turn his goofy charisma into national poll numbers.

"They're very good if you ask people, 'Would you like to go to the pub or have a meal with Boris Johnson?' They're not so good if you ask members of the public, 'Would you like Boris Johnson to look after your personal finances?' He's not trusted to do that," said Gimson.

Unlike Trump, Johnson is not anti-establishment. He is the establishment — educated at Eton and Oxford, alongside Cameron, although they disagree on Britain's place in Europe.

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