Diane Abbott said that failure in the West Yorkshire stronghold should spell “curtains” for Starmer, following the humiliating loss of Hartlepool
And she suggested that the party’s left could swing behind Greater Manchester mayor Andy Burnham as an alternative leader.
Meanwhile, Rebecca Long-Bailey, who lost out on the Labour succession to Starmer in 2020, said there would have to be “serious discussions” about the leadership if Batley and Spen falls to Tories.
No date has yet been set for the parliamentary by-election, triggered by former MP Tracy Brabin’s victory in the contest for West Yorkshire mayor earlier this month.
The seat, formerly held by murdered MP Jo Cox, has been Labour since 1997.
But Ms Brabin’s majority over her Conservative challenger in 2019 was just 3,525 votes - smaller than the margin in Hartlepool, which fell to Tories on a 23 per cent swing earlier this month.
And Tories will be hoping to scoop up many of the 6,000-plus votes which at the last general election went to the Heavy Woollen District Independents, founded by a local Ukip leader, as well as almost 1,700 won by the Brexit Party.
Ms Abbott’s comments came after Mr Burnham made clear he was ready for another tilt at the Labour leadership when it becomes vacant, having lost out in both 2010 and 2015. However an early contest might bar the former minister from taking part, as he is not currently an MP.
The close Corbyn ally told The Guardian that victory in Batley and Spen was far from certain.
“Support from the large minority ethnic electorate may enable the party to hold the seat and Starmer to hang on as Labour leader,” Ms Abbott said.
“But if Labour loses again, it must surely be curtains for him. And then it may be that Andy Burnham’s time will have come.”
Ms Abbott made clear that Burnham, who served in Mr Corbyn’s shadow cabinet and took no part in efforts to unseat him, would not be viewed as a toxic candidate by the left.
She said he was seen “by the largely pro-Corbyn Labour party activist base as a neutral figure: becoming mayor of Manchester also enabled Burnham to reinvent himself as a plucky insurgent, rather than a New Labour clone”.
Meanwhile, Ms Long-Bailey, who was sacked by Starmer in an early sign of his intention to shake off the hold of the party left, told ITV’s Peston: “I don’t want to lose Batley and Spen and I think the party and Keir and his leadership team, need to recognise where we’re at at the moment in terms of our footing with the electorate.”
Labour went into this month’s local elections “offering very little”, she said. “There was no policy other than focus groups, slogans and shiny suits, and that’s not enough to win the trust of the electorate. So we need to work very hard to develop policy and develop an offering and show the electorate what the Labour Party actually stands for.”
Pressed by Peston on whether Starmer’s future was at stake, she said: “I think there are going to have to be serious discussions if there is a loss in Batley and Spen but as I say I don’t want it to come to that, I want us to win that election. And I think if we pick a fantastic candidate, we’ll be in with a very good chance.”
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