For decades, Chingford has been synonymous with Conservatism. The London-Essex border seat was previously represented by Winston Churchill and Thatcherite outrider Norman Tebbit (“the Chingford skinhead”). Since 1992, its MP has been Iain Duncan Smith, the former Tory leader.

But at the 2017 general election, the Conservatives’ majority was cut from 8,386 votes to just 2,438. London’s traditionally blue suburbs – younger and more ethnically diverse than in the past – are turning red. The Labour candidate aspiring to oust Duncan Smith is Faiza Shaheen, the director of the Class (Centre for Labour and Social Studies) think tank and a proud Corbynite.

“Taking out IDS – every time I say that it makes me smile,” Shaheen, 36, confessed when we met recently at a café in central London. “The whole debacle of Universal Credit has increased food bank usage, and that does make him a hate figure. He personifies the cruelty and harshness of the cuts.”

Shaheen recalled the case of her mother, who died last year of heart failure and suffered the “indignity” of a benefits reassessment (despite doctors stating that she was unfit for work). “It was heartbreaking to witness that as her daughter.”

The Labour candidate, who won last month’s selection with 85 per cent of the vote, was raised in the constituency and attended Chingford Foundation School (whose alumni include David Beckham and Harry Kane). Her father, a car mechanic, grew up in Fiji and met Shaheen’s mother, a lab technician, in Pakistan while “on the run from the police”. “He was a really dodgy character, my dad. We’re always really confused, my brother, sister and I, about how we’ve turned out so straight.”

Shaheen’s father was violent and would sometimes vanish for long periods (once leaving the family without heating). But Shaheen credits him with developing her political consciousness. “My dad taught us a lot about race… I never remember a time that I didn’t know about empire.” Her childhood heroes were Muhammad Ali and Martin Luther King. Visits to Pakistan awoke her to global inequalities.

Shaheen’s mother, meanwhile, instilled in her the value of education. “One day she said to me: ‘Faiza, you’re going to go to the best university, it’s called Oxford’… I thought it was normal for mums to give their children these mad ambitions.”

Shaheen duly studied Politics, Philosophy and Economics at Oxford but was stunned by the snobbery and racism she encountered there. “People would pull a face at me and say ‘How come you speak like you’re from EastEnders?’” When Shaheen’s black friends visited, no one would sit with them in the dining hall. “I’d get so angry at people who had this insane sense of entitlement.” Shaheen later studied at the University of Manchester where she achieved a Master’s in research methods and statistics, and a PhD.

Though politicised from an early age, she did not join Labour until after Jeremy Corbyn became leader (having voted for him as an affiliated trade unionist). “I come from a Labour-voting family and I always voted Labour. But I felt frustrated that they wouldn’t be bolder, the most obvious example of that was Ed Miliband’s austerity-lite – it should have been ‘austerity is a lie and an ideological project’.” For Shaheen, Corbyn’s 2015 candidacy was a cathartic moment: “It was nice to hear someone speak honestly, the other people running at the time were so scared to say anything.”

Three years after that campaign, Labour appears irretrievably divided over anti-Semitism. Shaheen emphasised that “more needs to be done” but defended the leadership’s decision not to adopt the full guidelines issued by the International Holocaust Remembrance Alliance. “It’s pretty concrete: it’s trying to make sure that they [Labour] can come down hard on people who are being anti-Semitic. At the same time, they also need to make sure that people can fairly criticise the Israeli state over Palestine.”

Unlike Duncan Smith, a fervent Brexiteer, Shaheen backed Remain in the 2016 EU referendum (Chingford voted 51:49 for Remain). “There is truth in some of the sentiment about it [the EU] being an elite project, the European Central Bank doesn’t operate fairly, I think the euro was a mistake,” she said. “But the campaign was about immigration and I certainly wasn’t going to vote for the Nigel Farages of this world.”

Shaheen accepts that a second referendum may be needed to break the parliamentary deadlock but fears the consequences of a far-right resurgence: “It got ugly last time, and it gets ugly for people who look like me.”

Labour’s internal divisions over Brexit have led activists to threaten pro-Leave MPs Frank Field and Kate Hoey with deselection. “I support what local people want to do,” Shaheen told me. Does she favour the return of mandatory reselection? “It is a bit mental that you can be an MP for 30-plus years and never be reassessed. I think we should take a look at that, it’s about democracy.”

If elected, Shaheen hopes to regenerate Chingford (“the high streets that I grew up on are boarded up”), cautiously remarking that “it’s not a place where socialism necessarily comes across well – we’re going to have to be really smart about the way we talk to people”. But she observes with satisfaction that, having once been considered “crazy left”, she is now within reach of office. “I just thought I’d be frustrated forever.”