Boris Johnson loves being out on the election trail, transforming the atmosphere in a dull shopping centre on a Wednesday afternoon, hurling jibes at his opponents while confounding them with his magnanimity, making the political weather and providing irresistible copy for the reporters trailing in his wake.

On recent afternoons he has been hard at work transforming the atmosphere in the House of Commons, and today his efforts seem to have borne fruit, with his main opponents coming round to his view that there needs to be a general election before Christmas.

So we had the Prime Minister comparing Jeremy Corbyn in rapid succession to Fidel Castro, Goldilocks and Count Dracula, drowning his opponent in ridicule, horrifying those who think politics ought always to be conducted in solemn tone of voice but delighting the larger audience of irreverent and disregarded voters who like to see solemnity subverted.

There is a trenchancy about Johnson on the campaign trail, declaring that a Conservative Government can afford all the wonderful things it wants to do “because we believe in free markets and enterprise…in ways that cause a shadow of Transylvanian horror to pass over the semi-communist faces of the Front Bench opposite”.

Corbyn could not compete with such impertinence. He sounded underpowered as he said of the general election: “I”m ready for it. We’re ready for it.”

Labour, he promised, will show that “there is an alternative”, including “an alternative to sweetheart trade deals with Donald Trump”.

That sort of anti-Americanism is received wisdom in the circles in which Corbyn moves. It may be less popular in Middle England.

But nobody knows, and that is one reason why Johnson captivates audiences. He is doing something dangerous. His gambit may or may not succeed. He could go the way of Theresa May, who thought she could win an election, and found too late she couldn’t.

Corbyn, the disregarded Corbyn, may turn out to have a greater affinity with Middle England than the opinion polls suggest. He could be the underdog who was underestimated.

But if so, he this afternoon made a pretty good job of pretending to be weak.