Nigel Farage, the Brexit Party leader, is to join campaigners on the ground in Peterborough on Thursday as the party makes its final drive for a sensational by-election breakthrough which could deliver its first MP in parliament.

Sources close to Mr Farage were seeking to play down expectations of a runaway victory, describing bookmakers’ odds as tight as 1/7 on the Brexit Party as “nuts”.

But figures showing the Eurosceptic party scooped 16,196 votes in the city in the European elections – more than twice the tally of runners-up Labour – have fuelled anticipation of a dramatic upset in a seat that has for decades been a fiercely-contested Labour/Conservative marginal.

The by-election was triggered by the removal of former MP Fiona Onasanya in the first ever successful recall petition, following her conviction for lying about a speeding offence. She won the seat for Labour by a wafer-thin 607 votes over the Tories in 2017, with the Liberal Democrats trailing in a distant third.

Labour’s campaign was hit by their candidate Lisa Forbes being forced to apologise for “liking” a social media post that said Theresa May had a “Zionist slave master agenda”.

The Brexit Party’s Mike Greene was revealed to have made money from a firm that bought and sold freeholds in new homes in a practice criticised in a recent parliamentary report. But the party dismissed the issue, pointing out that Mr Greene was a member but not a director of the scheme.

Candidates in the Peterborough by-election Show all 15 1 /15 Candidates in the Peterborough by-election Candidates in the Peterborough by-election Mike Greene, Brexit Party Brexit Party parliamentary candidate Mike Greene during a Brexit Party rally at the Broadway Theatre in Peterborough, ahead of the upcoming by-election. PRESS ASSOCIATION Photo. Picture date: Saturday June 1, 2019. Peterborough is to hold a by-election on June 6 to find a replacement for MP Fiona Onasanya after she lost her seat through a recall petition. See PA story POLITICS Farage. Photo credit should read: Danny Lawson/PA Wire PA Candidates in the Peterborough by-election Paul Bristow, Conservative Party Conservative party candidate Paul Bristow talks to veterans during a D-Day 75th anniversary event in Peterborough as voting gets under way in the Peterborough by-election. PRESS ASSOCIATION Photo. Picture date: Thursday June 6, 2019. See PA story POLITICS Peterborough. Photo credit should read: Joe Giddens/PA Wire PA Candidates in the Peterborough by-election Lisa Forbes, Labour Party Labour Party candidate Lisa Forbes who will contest the vacant seat in the Peterborough by-election. PRESS ASSOCIATION Photo. Picture date: Thursday May 9, 2019. The city's by-election on June 6 will find a replacement for MP Fiona Onasanya who lost her seat through a recall petition after serving time in prison for lying about a speeding offence. See PA story POLITICS Peterborough. Photo credit should read: Joe Giddens/PA Wire PA Candidates in the Peterborough by-election Beki Sellick, Liberal Democrat Candidates in the Peterborough by-election Joseph Wells, Green Party Candidates in the Peterborough by-election John Whitby, UKIP Candidates in the Peterborough by-election Patrick O'Flynn, Social Democratic Party Patrick O'Flynn, Ukip Economic Spokesman and PPC for Cambridge delivers his speech during the Ukip Spring Conference at the Winter Gardens Theatre in Margate, Kent. PA Archive/PA Images Candidates in the Peterborough by-election Dick Rogers, Common Good: Remain in the EU Candidates in the Peterborough by-election Bobby Smith, Independent Candidates in the Peterborough by-election Tom Rogers, Christian People's Alliance Candidates in the Peterborough by-election Andrew John Moore, Independent Candidates in the Peterborough by-election Peter Ward, Renew Candidates in the Peterborough by-election Stephen Goldspink, English Democrats Candidates in the Peterborough by-election Pierre Kirk, UK European Union Party Candidates in the Peterborough by-election Alan "Howling Laud" Hope, Official Monster Raving Loony Party Leader of the Monster Raving Loony Party Alan 'Howling Laud' Hope who is his party's candidate for the Uxbridge and South Ruislip constituency in this year's General Election, in Westminster, London. PA

A spokesman for Mr Farage’s party said they were “fighting to win” and believed the result would be close. But he said Peterborough was 203rd on the Brexit Party target list and it would be a “fantastic” result to get within touching distance of victory.

The party had only turned its mind towards the Cambridgeshire constituency two weeks ago following the European elections, while Labour had been bussing in activists for months and using canvass returns dating back years to target its efforts, he said.

Labour is expecting a two-horse race with the Brexit Party, and insists it has not written off the seat. Betting odds appeared to be distorted by wagers from Leave enthusiasts excited by the European-election result, said one activist, who said: “It doesn’t feel like a runaway train. It’s going to be very close.”

Nigel Farage says the Brexit Party could 'stun everybody' in a general election

Despite the failure of Remain-backing parties to agree a joint candidate, the Brexit Party has used social media posts to try to present the contest as a rerun of the 2016 referendum, pitting them against the Liberal Democrats, who back a Final Say referendum.

Lib Dem leadership candidate Ed Davey, who was campaigning in Peterborough on Wednesday, said there was some evidence of Remain backers switching from both Labour and the Tories.

He acknowledged Peterborough was a long-shot for the party, which took less than 4 per cent of the vote in the last two elections, but did not rule out a shock, telling The Independent: “No result can be discounted.”