Boris Johnson's success leaves him vulnerable

The margin of success took his fellow candidates by surprise - but not the core of Boris Johnson's team.

After many, many weeks of private campaigning, introducing Boris Johnson to the world of the spreadsheet, this morning one of his organisers wrote the number 114 and sealed it in an envelope.

At lunchtime, the announcement revealed the controversial former foreign secretary had indeed received exactly that number.

That is not just a marker of the level of Mr Johnson's support, but for the sometimes clownish politician, whose reputation has risen and fallen and then risen again, it's a sign that it is different this time.

His campaign has extended way beyond his old friends. The discipline his lieutenants are trying to instil is holding at this stage.

But his success today leaves him vulnerable.

Frontrunner status is a precious commodity. It makes him the target for all of the others left in the race, for all of them to pitch themselves to those many MPs who feel strongly that he is wrong for the job.

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So members of his campaign team tell me their motto is simple - do not die. His place in the final two of the race to become our prime minister is secure, unless he errs explosively. With Boris Johnson, that is not a secure bet. And once in that final duet, weeks of scrutiny and challenge await.

There is a choice for those who want to stop him now. Discussions are live tonight between the other camps in the race over what to do next.

Should there be an effort to come together behind one candidate who could beat Mr Johnson?

Foreign Secretary Jeremy Hunt said tonight - arriving back at the Pall Mall mansion that used to be Mr Johnson's formal residence, of course - that he is the person to take him on. Although he had fewer votes than expected today, he's clearly not going to pull out.

Sajid Javid and Matt Hancock though, the home and health secretaries, met this afternoon after the results.

Sources close to Mr Hancock say he's "mulling over" what to do next. There's no final decision, but don't be hugely surprised if by Friday lunchtime he has withdrawn from the contest.

One of the only things we can be sure of: The next prime minister will be a man

Rory Stewart though is not going anywhere. He is instead ramping up his rhetoric against his fellow Old Etonian (yes, he and Boris Johnson did not just go to the same school, but also to the same Oxford college), and talking boldly about how only he can be the person to take him on.

Given his place on the political spectrum frankly that seems extremely unlikely, however many views his videos get on Twitter.

And while his team are extremely gung-ho, and he has built up some impressive momentum, some MPs from the so-called One Nation, (centre-ish) part of the Tory party are pretty cross, telling me that either Javid or Hancock had a decent crack if he would get out of the way.

There is plenty more of this political intrigue to come in the next week or so, whether it bores you to tears or is the insider manoeuvring that excites you. It's fluid, and there is, as I tediously probably always say, a long way to go.

There are two things we can be absolutely sure of, tonight Boris Johnson is looking hard to beat. And with Esther McVey and Andrea Leadsom both out of the race, the next prime minister will be a man.