Tory leadership race: Why are MPs lining up behind Boris Johnson?

Politics isn't always complicated. The reason why Matt Hancock, the health secretary, has backed Boris Johnson is plain.

He thinks he is going to be the prime minister and he wants to stay in the cabinet, with a big job. In the words of one source: "It was back him now, or in five weeks' time, so best to get on board."

There is another reason, though, that explains why he, other MPs and ministers have climbed on board the Johnson jalopy even if they have fundamental disagreements with him.

Plenty of MPs who worry about what he might do in office are joining his camp in order to stop him from veering off to the right - in the words of one, "to anchor" him in the middle ground. To be the Boris Johnson of City Hall in the late 2000s, not the Boris Johnson who has politically flirted with Donald Trump adviser Steve Bannon.

One minister joked that they were "wrestling with Boris Johnson's soul".

Tory members will ultimately, of course, be the ones who judge what that tells us about Boris Johnson himself. But other insiders suggest, scurrilously perhaps, an extra influence in play here too.

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It's notable how much friendlier the tone of the London newspaper, the Evening Standard, has become of late towards Mr Johnson, quite a move in its stance.

Who is the editor of that paper? Well of course, it's George Osborne, the former chancellor. A source said it had been made clear to Mr Johnson for several months by some of his colleagues that to make his leadership work he has to convince the middle of the Tory Party, not just the Brexit fringe, that he is up to the task. That "includes a former chancellor giving his blessing".

One well-placed insider detects the "hidden hand of George Osborne working with the Wizard of Oz" - Sir Lynton Crosby, the election strategist involved with Boris Johnson, who also ran campaigns for David Cameron and Mr Osborne over the years.

Former Chancellor George Osborne became editor of the Evening Standard in May 2017

Could that even mean a return for Mr Osborne one day?

He is not an MP any more of course, and is ensconced in being an editor of a paper. I'm told there have not been any conversations about any kind of return.

And this is, in a way, the ultimate kind of froth from the Westminster bubble. But if Mr Johnson wins, to survive he will need as much support as possible from every kind of Tory.