Figures shared with The Independent show that the organisation has increased its membership by 15 per cent since the beginning of 2018 and in the first four days of April alone Momentum gained an extra 500 members. It claims to be growing by an average of 1,700 new members a month.
The organisation also said that 95 per cent of its current funding comes from membership fees and small donations, with the average fee standing at £3 a year.
Set up in 2015 to support the values of Mr Corbyn’s left-wing leadership of the Labour Party, the group has become increasingly influential in recent months, with its founder Jon Lansman winning a place on Labour’s governing body – the national executive committee.
Momentum is not a political party itself and all of its members have to be fully signed-up members of the Labour Party, but the figures show its paying activist base is now larger than Ukip and the Greens.
Membership of the Green Party now stands at around 37,000 but a party source said that when members in grace are considered – those whose payments have lapsed – the figure is around 41,000.
Momentum’s national coordinator, Laura Parker, told The Independent: “With over 6,000 people joining our movement in the last three months alone, it’s clear the drive to get a social Labour Party elected and transform the country from the bottom up isn’t waning since the general election last year.
“Our focus now is on mobilising our 40,000 members to canvass for Labour in the council elections in May and developing the digital tools needed to facilitate mass-scale campaigning.”
Insiders now believe that if the current pace of growth continues, Momentum could overtake the Conservative Party figures by the next general election. The Conservative Party does not routinely publish its data and the last official figure of 149,800 was disclosed in December 2013. But it has been suggested the figure could now be considerably lower at around 70,000.
The latest figures from Momentum come after the organisation’s national coordinating group released a statement addressing the current antisemitism row in the Labour Party.
It acknowledged the anger of Britain’s Jewish community at the “numerous” cases of antisemitism within Labour and the party’s failure to deal with them “in a sufficiently decisive, swift and transparent manner”.
“Accusations of antisemitism should not and cannot be dismissed simply as right-wing smears nor as the result of conspiracies,” it added.
“Current examples of antisemitism within the Labour Party are not only a problem of a few, extreme ‘bad apples’ but also of unconscious bias which manifests itself in varied, nuanced and subtle ways and is more widespread in the Labour Party than many of us had understood even a few months ago.”
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