Boris's secret weapon could win him the leadership race

Could Boris Johnson be Prime Minister by Christmas? He seems to think it an entirely plausible denouement to the Brexit saga, judging by the manner in which he has emerged from the wings to take centre-stage this week.

Boris stole the limelight yesterday by telling Andrew Marr that he would withhold “at least half of the £39 billion” until the EU conceded his demand for a free trade deal that avoided a hard Irish border. He added: “And that is the way to, I think, put a bit of a tiger in the tank and to get these talks moving.”

The “tiger in the tank” was a curious metaphor to use for a politician born in 1964, the very year that Esso launched the advertising campaign of which it was the slogan. Was the infant Boris so impressed by the Esso tiger that it stuck in his memory? Or was it a phrase carefully chosen to appeal to the elderly electorate of Conservative Party members? And if the latter, who chose it?

Here’s a clue: Boris did not win two London mayoral elections on his own. His campaign manager both times was Sir Lynton Crosby, the “Wizard of Oz”. Back in 2013, Boris revealed Crosby’s secret to The Australian: “He works it out with all of his strange algorithms, polling, part sorcery, part science, and he presents you with this stuff that makes you focus on the things that really matter. He makes sure you are really connecting with what you say…”

Last September, The Sunday Times reported that Sir Lynton had dispatched David Canzini, one of his team at CTF Partners, to advise the European Research Group on their “Chuck Chequers” campaign. It has been running ever since and has helped sway more than a hundred Tory MPs against Mrs May’s deal. But Crosby himself, whose reputation here rests on David Cameron’s successful 2015 election campaign, has stayed focused on who has the potential to be Prime Minister. There are of course numerous Brexiteers who openly aspire to replace Theresa May: David Davis, Dominic Raab, Esther McVey and Priti Patel, not to mention candidates still in the Cabinet who have not declared themselves, such as Sajid Javid and Michael Gove. But the only one Crosby has any time for is Boris.

Over the past three months, Boris has kept himself in play while leaving the ERG, and in particular Jacob Rees-Mogg, to take the flak. Rees-Mogg is Boris’s only rival for the affection of the party faithful; significantly, he is the only other politician whom they invariably refer to by his Christian name: “Jacob”. But the ERG failed to offer a detailed alternative when Mrs May presented her Withdrawal Agreement to Parliament and subsequently failed to muster the necessary 48 names to force a leadership election. Though Boris has remained noticeably aloof from the ERG rank and file —indeed, he has never been popular in the Commons — he does have one advantage: Brexiteers have no other candidate whom the public knows much about.

Not that the public is impressed by the idea of Boris for PM. A weekend YouGov poll for the Sunday Times found that Boris is supported by just 22 per cent, while 57 per cent think reject him. But it is a safe bet that the 22 per cent include most of not all of the 100,000 or so Conservative Party members who would decide any leadership ballot.

Boris has been writing for this audience in the Telegraph for almost half of his 54 years. But Crosby has helped him to push their buttons in such a way as to position himself in their eyes as the only radical alternative to Mrs May — for example, by claiming last September that she had “wrapped a suicide vest” around the British constitution and “handed the detonator” to Brussels. This violent metaphor shocked the establishment and drew criticism from Sajid Javid, the Home Secretary, whom many see as the favourite to succeed the Prime Minister. But by associating him with a tough line on both the EU and Islamist terrorism, the image of the suicide vest helped Boris to consolidate his base.

For Boris, this week may be the moment of truth. If Mrs May resigns after a heavy defeat in the Commons, or if the 48 letters are delivered, Boris will certainly stand for the leadership. Only then will the dark arts of Sir Lynton be fully deployed. If Boris were appealing to younger voters, the tiger — an endangered species — would be a deeply inappropriate animal with which to associate himself. But Crosby is not squeamish about gunning for big game. He reportedly told Boris at their first dinner that “if you let us down, we’ll cut your f***ing knees off”. Boris bitterly regrets flunking the test of leadership immediately after the referendum. If he values his political future, he won’t want to let down Sir Lynton this time.