Boris vs. David: who will still be standing after the Brexit vote?

It turns out that Boris Johnson dyes his hair. Or so it seemed.

He was quoted admitting as much in an interview with the Sunday Times Magazine this week. But then, he called political editor Tim Shipman with an "urgent point of clarification." Said that his "yes" to the dye question was a joke that was misconstrued.

The prominence given to the matter, and to the reaction, was sad commentary on the level of the ensuing EU debate, now in its crucial, final week.

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The incident was also somewhat reminiscent of a much more significant, apparent about-face: the former London mayor telling colleagues he was "no outer," then suddenly deciding to become the Leave campaign's chief town crier.

That decision was no surprise to Sonia Purnell, author of Johnson's unauthorized biography Just Boris, who once shared an office with him when they were both journalists.

Sheand many otherssay Johnson only embraced the role of top Brexiteer when he realized it could offer him a back door into 10 Downing Street.

"He's a chameleon and whatever is to his advantage, to the advantage of his political career, goes," she said in an interview with CBC News.

"There is a sense of entitlement. He believes he's cleverer, more popular, smarter than [PM David] Cameron and therefore really the job should be his."

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The rivalry between the two Tories is well established.It is no secret that as Johnson left the London mayorship, he had hoped to replace Cameron, two years his junior and a former classmate at Eton.

But Cameron decisively held on to the Conservative party reins when he won a majority in the 2015election.

Still, the two would go head to head when, apparently sensing opportunity, Johnson jumped to the other side of the EU debate.

Obscuring the issues

The contest gradually became more personality-driven and more personal. Critics say that's taken away from real debate about the issues that should drive voters' decisions.

The two men couldn't be more different.

"Cameron is a quite sort of managerial person, he's not a populist," says Purnell.

Johnson, on theother hand, is "the great celebrity, the great performer, the actor if you like,the PR genius and the populist who can whip up a crowd, but who can get away with saying things that are patently untrue."

The duel has become such a pivotal narrative in the campaign it's been the subject of documentaries like Channel 4's Boris vs. David, countless articles,and even an untold number of menu items in British restaurants.

At The Diner in London's Soho district, the "Le Dave" burger is a French Charolais beef patty, with Swiss cheese in a brioche. The "Sir Boris," meanwhile, is made with British chuck steak patty with cheese and bacon, and a side of roast potatoes and gravy.

A Conservative civil war

The object for both men is to remain standing when the dust settles.

But the resultingand ongoing civil warwithin the Conservative party ranks could prove impossible to suspend even if Remain wins. Cameron would probably pay the price.

And if Britain votes to leave, Cameron, in the words of one prominent colleague, "wouldn't last 30 seconds."

"It would seem that [Cameron] simply couldn't be a unity candidate anymore, in which case how could he last?" says Purnell.

"So whatever happens there's going to be turbulence after next Thursday's vote."

And whatever happens, Johnson is positioning himself to take Cameron's place.

Johnson denies that, of course, and speaks of the need to heal the rift once it is all over.

But his ambitions, and the slightly flagging poll numbers for staying in Europe, have made Johnson the Remain campaign's favourite target.

Dice, a cigar and a drink

Last week, a new campaign poster depicted him throwing dice, flanked by fellow Brexiteers Nigel Farage, and Michael Gove, smoking a cigar and nursing a short drink, respectively.

The poster advises, "Don't let them gamble with your future."

Remain likes to also remind voters that the same man who decries the pro-EU "establishment" elites is an old Etonian-educated elite himself, who "once described the 250,000 a year he gets from the Daily Telegraph as chicken feed," said James McGrory, a Remain spokesman.

In a particularly pointed attack last week, fellow Conservative and energy secretary Amber Rudd said, "Boris is the life and soul of the party, but he's not the man you want driving you home at the end of the night."

The Boris effect is apparently perceptible in the polls, which have reflected growing support that is sometimes even ahead of Remain.

But it is not born of conviction, say some of those who know him.

"He enjoys the sound of shattering glass when he's caused the glass to shatter. He says it gives him that sense of power, which is obviously what he likes very much," added Purnell.

Johnsondenies that personal ambition is driving his campaign, which has focused on restoring Britain's sovereignty, as well ason the money Britain shells out to the EU and its infuriating bureaucracy.

Curbing immigration has also been an important theme and major motivator on the Brexit side.

Education Secretary Nicky Morgan this week accused the Leave campaign of a "mean-spirited" emphasis on immigration.

She then added, "The only thing that Boris and I appear to have in commonis that we both dye our hair."

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