A Survation poll published on Tuesday morning put Labour top with 26 per cent, up one point, with Nigel Farage’s party trailing with 24 per cent, down two points.

It followed the More in Common release on Monday, which put Labour ahead with 28 per cent compared to Reform’s 24 per cent. A YouGov poll gave both parties 22 per cent on Monday.

In another blow for Reform, Labour are eyeing a landslide victory in the Manchester mayor by-election, a contest called after Mr Burnham resigned from the position to pave the way for a return to Westminster.

He said: “There is no doubt there is a Burnham bounce and it has happened quicker than most of us expected.

“Part of it is Andy Burnham himself – his policies and communication. And part of it is that Keir Starmer is no longer there.

Lord Hayward pointed out that the Tories are in third place in the polls but are now closing the gap on Reform, with Survation putting Kemi Badenoch’s party up two points to 21 per cent.

He said: “We are no longer talking about Reform becoming the government – in fact, there is an open question over whether they are the natural party of the right.”

But he warned: “This is normal. The only new prime minister not to get a bounce in the polls was Liz Truss. When Gordon Brown replaced Tony Blair it was worth seven points, Theresa May had four points when replacing David Cameron, Boris Johnson six points when replacing May, and Rishi Sunak four points after replacing Johnson.

“The question for Andy Burnham is how long this will last and only time will tell on that.”

He said Labour were still “neck and neck” with Reform, but added: “Labour have definitely been given a second chance.”

Mr Farage is currently bogged down in a by-election in Clacton after resigning his seat to trigger a vote. An investigation into a £5m donation from crypto billionaire Christopher Harborne is hanging over his head, as well as another into gifts and support he received from convicted money launderer George Cottrell.

Prof Curtice noted that, since Mr Farage called his by-election in Clacton on 6 July, Reform had dropped an average of three points in the polls.

He also noted the Tories are averaging 20 per cent for the first time in a year – describing it as “a mini revival.”

He added: “Most of Reform’s votes came off the Conservatives – so that means the Conservatives are getting votes back off Reform.”

Lord Hayward also said that Mr Burnham “is using August very well, just as Nigel Farage did last year” with a series of announcements and social media videos putting Labour on the front foot.

“In contrast, Reform don’t seem to be able to do anything that can halt their decline,” he added.

Luke Tryl, director of More in Commons, said: “No doubt Burnham’s first week cut through and he was able to own the attention economy and look like he got it in a way Starmer struggled with that has brought some disillusioned progressives back to the fold.

“At the same time Reform’s bad couple of months have meant there are voters on Labour’s right who are willing to give the party under Burnham another look.”

According to polling from More in Common, Labour’s candidate for the mayor of Greater Manchester, Bev Craig, would secure 39 per cent of the vote on Thursday, while Reform is expected to gain around 19 per cent. The Greens are currently in third place with 14 per cent, with the Tories on 12 per cent.

In the subsequent run-off, Labour would get around two-thirds of the votes against Reform, according to the poll.

When the contest began, Reform were the narrow favourites after the local elections showed they had the highest level of support in Greater Manchester.

Local election results on 7 May in the region gave Reform 30.8 per cent, Labour 23.6 per cent, the Greens 19 per cent and Conservatives 10.4 per cent.

A Reform spokesperson insisted that the party is “calm” about the turn in polling.

The spokesperson said: “We expected Labour to go above us; we are calm about it. Let’s see where everyone is by December.”

In a note on how things can change, the spokesman added: “Two years ago Keir Starmer was flying high in the polls, comment pieces were talking about him being a sex symbol and the ‘grown ups were back in charge’.”

After winning the Gorton and Denton by-election earlier this year, the Greens have been hit nationally over questions about antisemitism as well as allegations about their leader Zack Polanski. Reform have referred Polanski to the police over a post on X apparently linking Mr Farage to a guillotine.

Meanwhile, Mr Burnham said he would not get “carried away” but was pleased to have “connected with people” after a poll gave Labour its first lead for more than a year.

The prime minister told reporters on a visit to Portsmouth: “I wouldn’t get carried away by any poll. I’m pleased to have made a start where hopefully I’ve connected with people.

“And I am talking a lot about Britain believing again and getting its hope back, and I’m not going to apologise for that. I think we should have a bit more of a spring in our step.”