Liz Kendall has rejected calls to quit the Labour leadership contest to stop the left-wing MP Jeremy Corbyn winning the election.
The shadow care minster, who is seen as the Blairite candidate in the race, has come under increasing pressure to pull out and throw her support behind Yvette Cooper or Andy Burnham to ensure one of them wins enough mainstream votes to beat Mr Corbyn.
But speaking this morning, she said: "You never stop fighting for what you believe in." Leadership rival Yvette Cooper backed her decision to stay in the race, saying they must not “leave it to the boys”.
It came as Lord Mandelson, an architect of New Labour and former Business Secretary, warned that Labour’s “existence as an electoral force” depended on denying Mr Corbyn winning the contest, predicting that a win for the hard left candidate would leave Labour in the wilderness of opposition for more than 15 years.
A growing number of voices are calling on Ms Kendall to stand aside after the first public poll of those eligible to vote found Mr Corbyn with an astonishing 17 per cent lead over second-placed Andy Burnham, with Ms Kendall trailing in fourth place on just 11 per cent.
However Ms Kendall insisted she had no intention of pulling out of the race and her supporters said Mr Burnham and Ms Cooper only had themselves to blame for Mr Corbyn’s growing appeal. Her team said it would make no difference if Ms Kendall stepped aside, saying she and Mr Corbyn were not vying for the same votes.
The BBC's Norman Smith asks Liz Kendall if she'll stand aside from the Labour leadership contest. https://t.co/0IwNUkA0NC— BBC Politics (@BBCPolitics) July 23, 2015
Asked whether she would quit the race to block Mr Corbyn from winning, a spokesman for Ms Kendall’s campaign said: "It's not going to happen. This briefing is nonsense because in a preference vote it doesn't matter how many candidates there are," a spokesman said.
"This is deliberate misleading briefing that says more about Andy and Yvette's problems following their flip-flop on welfare.
"But more than that, we're in this to win. Liz is going to continue setting out how she believes Labour can win again in 2020 if we make the right choices now."
There is a growing concern to those on the right of the Labour movement of the consequences of a Mr Corbyn win.
Lord Mandelson suggested the party was still struggling to deal with the “terrible legacy” left by Ed Miliband.
"Those of us who stayed and fought to save the Labour Party in the 1980s will be experiencing a growing sense of deja vu," he told The Times.
"The last five years have left us with a terrible legacy to overcome with the existence of the Labour Party as an effective electoral force now at stake."
In a leadership hustings last night, Ms Cooper, Ms Kendall and Mr Burnham were asked whether they would serve under a Mr Corbyn leadership. Only Ms Kendall said no, with Mr Burnham surprisingly saying he would.
Ms Cooper refused to rule out the prospect and this morning she told the Today programme: "If you are involved in politics and believe in the Labour Party, you shouldn't just take your bat and ball home.”
Ms Kendall was rather more unequivocal."I think it would be disastrous for the party, it would be disastrous for the country, we'll be out of power for a generation," she said of the thought of Mr Corbyn leading the party into the 2020 election. "I don't want to be a party of protest and I wouldn't be able to stop myself from making that case."