Lisa Nandy has warned that Labour is facing its “last chance to save the party” as she lay the ground for her campaign to become next leader.
The Wigan MP said she was “seriously thinking” of running to take over from Jeremy Corbyn after Labour's crushing election defeat.
In an interview with the Mirror in Bury North, now the most marginal seat in the country, she said she needed “a bit of time” to speak to voters before her final decision.
But she is expected to have met the threshold of MPs and unions required to secure a nomination for the race in which she could face Labour figures including Keir Starmer and Becky Long-Bailey.
Ms Nandy urged the party to come together, rather than descending into in-fighting, and focus on rebuilding the “red bridge” between its original heartlands and metropolitan areas.
“This is genuinely the moment when we decide whether we want to save the Labour Party. This isn't an argument about saving it from one faction or another,” she said.
“It's about whether that traditional coalition that has propelled us into power three times in the last 100 years can hold good, and whether we can speak for both Lewisham and Leigh.
“It's been a very long time coming. We've lost older voters, non-graduates and many working class voters. In the end, they felt that Labour had left them.
“That's the electoral challenge. We need to think seriously about how we speak for both.”
After Mr Corbyn led the party to its worst defeat since the 1930s, leaving the Tories with a majority of 30, many Labour insiders fear they will be out of power for another decade.
Ms Nandy claimed there was a path to winning the next election in 2024 but admitted it would be difficult after the scale of the defeat.
“There was no enthusiasm for the Tories and no real affection for Boris Johnson ,” she said.
“He has learned all the wrong lessons from this victory. These votes weren't earned, they were lent, and unless he does something with them he will find himself in a really difficult position.
“People in Northern and Midlands towns have heard this before. George Osborne had a huge push on devolution of powers and funding and most of it hasn't materialised ten years later.
“If they don't deliver it, having talked a good game in the election, then they'll find themselves in trouble in five years' time. There is a vacuum there into which Labour can and should step.”
Ms Nandy plans to spend the next few days knocking on doors in Leave-voting former Labour heartlands before deciding whether to throw her hat in the ring.
“I'm seriously thinking about it. But I do need a bit of time to listen to what people have been telling us. Anyone who turns around and says I know how to fix it and I'm the right person to do it, probably hasn't got the humility it takes to rebuild the party and win back people's trust.
“If at the end of that process I feel that I can do that, that I do know what has gone wrong and that I do have an understanding of how to put it right, then it would be a duty to run.”
Ms Nandy, who voted Remain but believed in delivering on the referendum result, said it was “very unlikely” she will support Mr Johnson's EU withdrawal bill in tomorrow's vote as he wanted a hard Brexit .
“It's really hard to overstate how much is up for grabs now and how much is at stake if we get this wrong,” she said.
With the PM pushing for a close trading relationship with the US, workers' rights like the minimum wage and health and safety laws would be on the table.
“What we do now is really important. There is an opportunity for the Labour party. Rather than turn inwards and start to fight amongst ourselves, we haven't got time to waste, the next few months are going to be critical.
“As we approach the next general election , were we complicit in a hard Brexit, or did we stand together and do everything in our power to defeat it?”
The Wigan MP, whose seat voted Leave, claimed that she had “got a lot of grief” for trying to reach a compromise on Brexit – and had supported Mr Corbyn's efforts to do so.
“I was arguing for a position that - for all the vocal shouty people on each extreme - most people desperately want.
“Whether you leave or remain I care more about whether this country pulls together and moves forward together.”
She warned: “Unless you bring those two sides back together there is absolutely no hope for forming a majority Labour government.”
Ms Nandy said much of Corbynism should be preserved – crucially the rejection of an economic model that only worked for a few, and “being brave enough to wear our values on our sleeves”.
“These are really important things that we need to hang onto. The risk is that you take the things we got right and throw them out with the things we got wrong.”
But she admitted that Mr Corbyn's name had been a problem on the doorstep in areas like hers.
“There is large element of Jeremy that is a pacifist at heart. Whether he meant to or not, he gave the impression that he was careless about national security.
“In Wigan there's a very strong sense of pride in what the people of the town have done, what they've sacrificed. It is young people from places like this that go off and fight wars.
“Rememberance day and armed forces day are a big deal and it's a basic question of respect.”
She said Labour had to take a “zero tolerance” approach to anti-semitism and that delays in high profile cases had been “very damaging” to its reputation as an anti-racist party.
“I don't know whether it was chaos or conspiracy. I cannot fathom why it would take so long to deal with those incidents. It was outright racism and it should have been dealt with then and there.”
She suggested Labour should adopt all the recommendations of the Equality and Human Rights Commission report into alleged institutional anti-semitism.
“We should do everything that is required of us in order to start to rebuild that trust with the Jewish community and the wider public.”
The MP claimed that some of Labour's manifesto priorities at the election “just didn't make sense to people” - for example rail nationalisation in towns that relied on buses.
She suggested the manifesto had been too broad. One voter had told her: “Don't promise what you can't deliver, because it's our money and we don't have a lot of it.”
It came as shadow foreign secretary Emily Thornberry yesterday became the first MP to formally declare they planned to enter the contest.
The Islington South MP revealed she had warned the Labour leadership that backing a Brexit election would be an “act of catastrophic political folly”.
She dismissed claims the next leader had to be from the North, arguing that “political nous and strategic vision” were more important.
