"The trouble is, I’m not an outer". These words may not have quite have the import of John F K’s “Ich Bin Ein Berliner” or Martin Luther King’s “I have a dream”. But when the history of British politics in the 21st century comes to be written, that statement may feature prominently.

According to today’s Daily Express, it was made by Boris Johnson in a meeting with Eurosceptic Tory MPs just before Christmas.

"In what many will see as a setback to the whole campaign, he made it clear he did not want to lead the Brexit drive," writes David Maddox. "It is understood he said: 'The trouble is, I am not an outer'. Mr Johnson was widely considered a Eurosceptic."

The story contains the usual health warnings. There was no confirmation from Johnson himself. It’s clear the meeting – if it actually took place – was briefed by someone from outside the Johnson camp. His words could have been misinterpreted, or simply made up.

But the article has a ring of truth. And it has a ring of truth for this simple reason. Boris Johnson is genuinely not an outer.

Over the past few months I’ve been fascinated – and perplexed – at the attempt by Tory eurosceptics to rebrand The Blonde Bombshell as The Blue Rinse Bombshell. He would be their champion, they insisted. The ideal bearer of the standard of Little England. A thinking man’s Nigel Farage.

And in fairness, Boris has lead them on a little. A slightly more robust tone on immigration here. A witty put down of the French there.

But all the while he has known – as I suspect the outers have secretly known too – that he would be the worst spokesman for the eurosceptic cause. Boris Johnson is a good old-fashioned moderniser. What’s more, he is a moderniser who has spent the past eight years as mayor of London, the pounding financial heart of Europe. The idea that he could – with credibility – lead the drive for separation from Europe is, and has always been, a eurosceptic fantasy.

Which doesn’t mean he couldn’t lead it without credibility. The man who proudly sported a pink cowboy hat as he marched in London’s gay pride parade could stand arm in arm with Ukip’s leader as he issues demands to seize back control of our borders so we can slam in the face of HIV sufferers. But in an era when authenticity is the currency of politics, it seems unlikely Johnson would squander his hard-won political capital in pursuit of a cause he doesn’t believe in.

The eurosceptics, aware of this, have of course been trying to tempt him with a cause he does believe in – namely the succession to David Cameron. “"Be there for us," they have told him, "and we will be there for you when the time comes”. But – for the moment at least – Boris Johnson prefers to maintain a discreet distance. He appears to have calculated, correctly, that a Faustian pact with the hard right of the Tory party would be a pact too far.

All of which reveals something about those who had been hoping – and briefing – that they intended to use the European referendum, and the subsequent Tory leadership contest, as a way of calling a halt to the great Cameron modernisation project. Like those Labour MPs hoping to resist the Corbynite take over of their party, they haven’t got a candidate.

In response to Boris Johnson’s rejection of their advances, one bullish Tory MP said, “Whether we win or lose [the referendum], the next leader of the Conservatives will be a eurosceptic”.

Which is fighting talk. But precisely who is this knight in Thatcher-patented armour? Some point to Theresa May, and attempt to frame her as the Boudica of the Shires. The problem is, George Osborne is busy pointing them towards Theresa May too.

"Theresa is George’s secret weapon", one Tory MP confided in me. "He knows she doesn’t have any sort of base amongst the backbenchers or the wider party. His strategy is to try to help Theresa onto the ballot as a way of keeping Boris off."

Others talk hopefully of skipping a generation, and anointing rising star Sajid Javid. But Javid has made up his mind to play a longer game, and told friends his currently strategy is to move in behind Osborne.

Phillip Hammond’s name is occasionally mentioned. And then swiftly discounted. Whilst regarded as politically competent, the foreign secretary has inherited Michael Howard’s 'something of the night' aura.

"The problem with Phillip is whenever you see him on TV he gives off the impression if he stood next to a mirror he wouldn’t cast a reflection," one Eurosceptic MP conceded to me.

There is even wistful muttering about Liam Fox, a man with impeccable “traditionalist” credentials. But he enjoys almost no profile amongst the wider electorate, save for the occasion as defence secretary when, in his own words, he allowed the distinction between his personal interests and his government activities to "become blurred".

The eurosceptics have been attempting to use their dialogue with Boris Johnson to highlight their strength.

"If you want to be Tory leader, then you have to come and pay your respects to us," has been their message. But in reality, it has merely underlined their weakness. And underlined that there is currently no-one on the right of the Tory party who can credibly appeal to Conservative MPs, Tory activists and the electorate at large.

On one level none of this matters. Labour’s implosion means that whoever is elected as David Cameron’s replacement will be prime minister after the 2020 election. But if the only hope for the Tory right is to anoint Boris Johnson as their candidate, then David Cameron’s modernisation of his party is almost complete.