The Liberal Democrat leadership race is on a knife-edge with postal votes cast splitting "almost 50-50" between Jo Swinson and Sir Ed Davey, The Independent has learned.
The figures were described as "a major surprise" by a source at the party's headquarters - given Ms Swinson has been the odds-on favourite to win the contest on Monday.
One supporter of Sir Ed's campaign said he was now in a strong position, arguing he was gaining an edge the longer the race to succeed Vince Cable has progressed. "It really is game on now," the backer said.
The Lib Dem source said: "Postal ballots were counted and verified on Friday. There was a major surprise as it showed an almost exact 50-50 split, although Swinson is the clear bookies favourite."
Around 60 per cent of the Lib Dems' 107,000 members had voted at this point. However, only a minority of votes were by post - and therefore split down the middle.
Nevertheless, if the postal returns are matched by votes cast electronically it points to a much closer race than expected at the outset, when Ms Swinson was the clear frontrunner.
Although little divides the two candidates on policy, critics say she has appeared more hesitant in the many hustings, including a live BBC TV debate on Friday.
His opponent has called for local pacts to allow a single pro-Final Say referendum candidate a clean run in marginal constituencies, to maximise representation in the Commons.
Sir Vince will bow out on a high, after his party's remarkable recovery at the May local and European parliament elections, made it unquestionably the leading Remain force.
And the new leader is likely to enjoy an early present with victory in the Brecon and Radnorshire by-election on 1 August, slashing the Tory majority to just three.
"Since then, Ed has been getting much more in the media and has got the better of Jo on policy and substance in hustings up and down the country. It really is game on now."
A Lib Dem spokesperson said: "No counting has taken place so comments such as this can't be anything other than pure speculation."
If you are still yet to cast your vote, you have until 13:00 Monday.
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