Ask a young Labour supporter why they back their party and a small vein will stand out on their forehead at the audacity of the question. Tory voters under 35, by contrast, will look drained. Then they will try to deny it. “Well yes, I have voted Tory, but I’m not a Tory,” one friend shiftily told me.

Those actually prepared to identify as young Conservatives are hard to spot, if only because they tend to disguise themselves, chameleon-style, as old ones. Tory conference last year was full of teenagers wearing signet rings and three-piece suits, hoping for a selfie with Jacob Rees-Mogg. (Labour conference meanwhile had 50-year-olds dressed as students.) But youths of this sort are rare.

A new piece of research commissioned by