Milani is also determined to harness the youth vote. "There’s no-one who can turn out student votes like I can," he says. "My vision has always been we can do here what students in Sheffield did to Nick Clegg." He is planning a big student voter registration drive at Brunel in September and says a general election in term time, when students will vote here rather than at home, would be a big boost to Labour.

Johnson is among a number of senior Tory MPs in marginal seats being targeted in Momentum’s "Unseat" campaign, amid speculation that the Brexit crisis could spark an election within months (both Milani and Evenden-Kenyon believe it will take place this autumn).

Also in the group’s sights are Iain Duncan Smith, who has a 2,438 majority in Chingford and Woodford Green in north London, Grant Shapps, with a 7,369 majority in Welwyn Hatfield in Hertfordshire, and Amber Rudd who has a wafer-thin majority of just 346 in Hastings and Rye, East Sussex.

Tories are outwardly putting a brave face on this, with one MP telling BuzzFeed News that the Conservatives have actually had better than expected local election results in areas where Momentum have held rallies – because it reminds voters why it is so important to turn out and vote to "make sure Labour is not elected".

But Milani is confident that Labour can beat Johnson, whether the Brexit Party stands or not. "I think we can beat him one on one, genuinely," he says. "People feel powerless – there’s a small group of Tory members who will make him PM – and we’re saying no you’re not powerless, we can unseat him here, this is all the power in the world."

Momentum is also quick to point to research which they say proves there are growing numbers of young voters in Uxbridge who are more likely to vote Labour.

The data is in a report from Tory renewal think tank Onward earlier this year. It measured the ratios of younger (aged 20-39) to older residents (60 plus) by constituency and found that a seat is likely to be won by a party other than the Conservatives if the ratio rises above 1:1.

The report said 242 seats currently meet that criteria, of which 54 are held by the Tories – and some, including Uxbridge, had ratios that were "far higher than the tipping point, suggesting they are vulnerable if age continues to be a predictor of vote intention".

Latest figures from the House of Commons library show that over 33% of the constituency’s population is between the ages of 20 and 39, compared to just 17% over 60. Housing developers are racing to build more apartments in the area, as sky-high prices in London push the under-40s out into the suburbs.

The seat has also become more ethnically diverse in recent years, according to Labour. Data from the 2011 census, the latest available, shows the local population was 70% white, 18% Asian and 6% black.

Momentum hope to capitalise on this, not only because black, Asian, and minority ethnic (BAME) communities historically vote Labour, but because Johnson has repeatedly been forced to apologise for his use of language about Muslim and black people. One local Tory insider admitted Johnson’s past remarks could be a challenge with BAME voters on the doorstep.

Yet Milani has faced his own controversy over racist language. He has been exposed for a string of anti-Semitic tweets posted between 2011 and 2013, including the message "Nah u won’t mate it will cost you a pound #jew".

"I was a teenager," he says. "I unreservedly apologise and I will continue to do so as long as people ask me about it. I’m deeply embarrassed about it." He insists he has been working with Jewish communities to get "more anti-racist education" in schools and universities. Would that have helped him? "Of course – the language that we used, we had no idea of the context," he says. "We thought it was banter. The same way kids call each other gay in the playground, not realising the harm that does to people."