The first poll of Labour members put shadow Brexit secretary Mr Starmer narrowly ahead. He was also ahead in nominations from MPs and MEPs, garnering 88 signatures to Ms Long Bailey’s 33. But on current standings Mr Starmer would lose, with 49 per cent to Ms Long Bailey’s 51 per cent.

Survation also predicted that shadow education secretary Angela Rayner would win the deputy leadership contest with 60 per cent of the vote. Ms Rayner also got Momentum’s backing. In first preference votes, Salford and Eccles MP Ms Long Bailey would win 42 per cent to Mr Starmer’s 37 per cent, according to Survation — in the second poll carried out so far in the contest.

Survation asked Labour List website readers for their preferences and weighted the results to reflect the membership. The poll indicates that Ms Long Bailey, considered to be Mr Corbyn’s “continuity candidate” is most popular with around 500,000 Labour members who will decide the contest along with supporters who pay a £25 fee. Jess Phillips would get 9 per cent of first preferences, Lisa Nandy 7 per cent and shadow foreign secretary Emily Thornberry 1 per cent.

The final postal ballot will be carried out using a transferable-vote system, with members able to list their candidates in order of preference from one to five. If no candidate wins a majority on the first count, the MP in last place will be eliminated and their votes redistributed according to their second preference, with the process continuing until one candidate secures a majority.

According to the poll Mr Starmer would bag at least 60 per cent of second preference votes from Ms Phillips and Ms Nandy if they are knocked out, but this would not be enough to beat Ms Long Bailey.

Candidates are due to start leadership hustings, with the first event scheduled in Liverpool. In order to progress to the postal ballot of members and supporters, candidates must get the support of 5 per cent of constituency Labour parties or three affiliates, including two unions, by February 14.

Mr Corbyn’s successor will be announced on April 4. (IPA Service)