Sadiq Khan’s campaign are increasingly bullish about securing victory in the race to become Labour candidate for the Mayor of London, with claims that the Tooting MP has gained momentum as ballots are dispatched.

A Survation poll yesterday showed Khan has better name recognition than any potential Conservative candidate, and has a healthy 50%-37% lead over Zac Goldsmith – increasing Labour’s vote by more than Goldsmith increases the Tories’. Khan has also secured the support in recent days of influential London issues journalist Dave Hill, and the number of MPs supporting his bid has risen to 16, with the recent additions of Keir Starmer and Ruth Cadbury. His odds with the bookmakers have been slashed to 11/8.

However, it is the influx of new members and supporters that has given the Khan team such confidence. There are believed to be around 20,000 registered supporters and a further 20,000 new members in London, and a source from Khan’s campaign has told LabourList that they believe the percentage of new sign ups supporting frontrunner Tessa Jowell is negligible. They still accept Jowell will win most first preferences, and that the contest will go to a final run-off between her and Khan, but are adamant that it is their candidate who now has the best chance of victory. A source told LabourList that their canvassing showed support for Khan had increased, and that the second preferences of Diane Abbott would see them over the line.

They canvassing returns apparently show an effective “four way electoral college”, of old members, new members, registered supporters and trade union affiliates. The only strong victory for Jowell is among old members, it is claimed.

Unsurprisingly, Jowell’s campaign contest these ideas, claiming that their canvassing returns had stayed steady throughout the campaign, and they remain “confident, but not complacent”.

A Jowell campaign insider argued that a narrative had built up around the leadership race that none of the four could win in 2020, which has in part led to the support for Jeremy Corbyn, but no similar belief was in place around the Mayor of London election. They contest that voters in London were still backing the candidate they believe has the best chance of winning next May, and that last week’s YouGov poll, showing Jowell ahead of Goldsmith but Khan behind, proved that was Jowell.