The hugely influential Unite union is set to have its first female general secretary after a ballot to decide the successor to Len McCluskey.
Voting papers will be formally counted on Wednesday, but Sharon Graham, an assistant general secretary of the union, is expected to win.
It is believed she has achieved a few thousand more votes than Steve Turner, who had been tipped as the favourite candidate.
It is expected that the other candidate, Gerard Coyne, will come third.
A spokesman for Graham’s campaign said: “The sampling of the vote is going on. The more it goes on, the better it looks for us. Of course we will only get the result when the count is finished.
“But we are confident Sharon is going to win. If she does, it will be an historic victory for the campaign and the workers in Britain and Ireland.”
The official announcement of the ballot result had been due on Thursday but statements from the candidates confirming the votes are expected on Wednesday.
Graham leads Unite’s Organising and Leverage Department, which specialises in taking on hostile employers.
She has led recent disputes at British Airways and Crossrail as well as campaigning to unionise Amazon, describing herself as the “workers’ candidate” and pledging to take Unite “back to the workplace”.
Graham – who is backed by the Socialist Workers Party and the Socialist Party – has said she wants to rebuild the union as a movement which delivers industrially and politically.
Momentum, the grassroots campaign group set up after Jeremy Corbyn became Labour leader, said it welcomed Graham’s apparent victory.
“Unite members have made their voices heard,” co-chair Gaya Sriskanthan said. “They want a union that organises, that builds power in the workplace, and that uses its leverage to take on bad bosses.”
Sriskanthan added: “Sharon campaigned on that promise and we fundamentally agree that any route to progressive change in Britain requires working class organisation to be stronger than ever before. We look forward to working with Unite and our allies across the Labour movement to achieve that goal.”
Despite her strong left-wing credentials, Graham has said she does not want to engage in constant in-fighting with Sir Keir Starmer. Speaking last month, she said: “Labour will likely be in opposition for most of the next decade and workers can’t afford to wait…we can be more effective by ridding ourselves of the obsession with fighting yesterday’s wars within Labour.”
But she warned that the party can not be guaranteed Unite’s financial backing, saying she prefers “payment by results” – and warning Starmer there would be “no blank cheque”.
Speaking about the election campaign, Graham said: “My slogan all along has been ‘Back to the workplace’ to build the union to fight for jobs, wages and conditions.
“That has been rewarded with huge support for me in big industrial branches like Hinkley Point, London construction, Ireland construction and Vauxhall.
“My campaign co-ordinators estimate that my branch nominations cover a potential voting base of 250,000 members – and that’s before the 300,000 women in the union have had their say.
“I am not a member of any Unite or Labour faction – other than my own supporters group. Unite members at the workplace want real change, not a settling of old scores or a Westminster rematch.”
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