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Labour leadership candidate Jeremy Corbyn was urged by one of his most senior supporters to withdraw from the contest - but the message was rebuffed, the BBC understands.

BBC political editor Laura Kuenssberg said the supporter told the left wing MP "a few weeks ago" he had not entered with the intention of winning.

"The message was, this has gone far enough, time to stop", she said.

Mr Corbyn's campaign said he was standing to be the next prime minister.

"The question is, who will be the Tory candidate?" a spokeswoman added.

His team would not confirm such a conversation took place, but would not deny it.

Analysis by Laura Kuenssberg, BBC political editor

This gives an intriguing picture of how despite the hype, even some of his senior supporters have concerns about his mission and its long term impact on Labour's fortunes. As the former Foreign Secretary, Jack Straw, who knows Corbyn well, suggested, perhaps the person who is most terrified about Jeremy Corbyn winning is Jeremy Corbyn.

Despite the clamour of the summer, there is not enough reliable data, nor understanding of the implications of the new expanded electorate to predict the result with any confidence.

And in the last couple of weeks the fizz has gone out of the Corbyn campaign and both Yvette Cooper and Andy Burnham's teams report support coming their way.

But if Mr Corbyn does win, he may well be haunted by a sense that he didn't really want the job in the first place.

Read more on Laura's blog

The left wing MP entered the leadership contest as an outsider, but has become a frontrunner, triggering warnings from senior party figures about him winning.

It is the final full day of campaigning in the contest to succeed Ed Miliband as Labour leader, with Andy Burnham, Yvette Cooper and Liz Kendall all hoping to defeat Mr Corbyn.

'Tory shires'

Mr Corbyn, who became a Labour activist while working in Shropshire, has said he will seek to broaden the party's electoral appeal, insisting there can be no "no-go areas" for the party.

"If I am elected leader I will ensure that Labour is as much a party in the communities like the one in which I was born, as it is for people in inner-city constituencies like the one I represent," he wrote in an article for the LabourList website.

"Too often the old machine politics writes off "the Tory shires", abandoning communities struggling with issues such as housing costs, public service cuts and social exclusion just as those in inner cities are. If Labour doesn't offer those communities solutions, no one else will."

Voting closes at 12:00 on Thursday, with the winner announced on Saturday.

Amid reports that some people have yet to receive their ballot papers, Mr Burnham's campaign manager has criticised the party for closing a helpline for people trying to vote in the contest.

Michael Dugher, the MP for Barnsley East, said this was "unbelievable" but Labour said the helpline had been replaced by a recorded message explaining how to vote.