Senior Labour figures have expressed concern that the growing parliamentary support for the two leadership frontrunners has left the potential modernising candidates struggling to gather the 35 nominations they need to make the ballot paper.

The shadow health secretary, Andy Burnham, and the shadow home secretary, Yvette Cooper, are understood to have secured more than 100 nominations between them, while the shadow education secretary, Tristram Hunt, is yet to declare because he is well short.

Liz Kendall’s allies insist they have the required numbers, but expressed concerns at weekend reports from allies of Burnham that they plan to attract so many nominations that some candidates are excluded.

Senior voices in the party are now warning that the concentrations of the nominations among two candidates could prevent others from standing and restrict the debate about what type of leadership is needed. One senior backbencher, Barry Sheerman, claimed that Unite supporters were pressurising new MPs to back the frontrunners.



Lord Hutton, a former Labour business secretary, said: “Labour is facing a very deep crisis and can no longer exist to appeal to a diminishing trade union vote. We need a big debate we have been of deprived for the past five years and that requires more than two candidates. I have already said we need to skip a generation, and MPs have a duty to provide a real debate that it so badly needs.”



Lady Morgan, a Labour peer and adviser to Tony Blair for 10 years, said: “We have just suffered a catastrophic election defeat and need the widest possible debate about how we rebuild support for the party. To try to close down that debate prematurely is both arrogant and plain wrong.”

She pointed out that in 2010 David Miliband ensured some of his supporters nominated the leftwinger Diane Abbott to ensure she made the ballot paper.



There is a frustration among some candidates that so many MPs have been signed up even before the first hustings has begun, suggesting they have already decided how to respond to the election defeat.



Under a rule change introduced in spring 2014 abolishing the old electoral college, any leadership candidate now needs to be nominated by 15% of the parliamentary Labour party, and not the previous 12.5%. The proportion was increased because the new election system ended an electoral college that gave MPs one-third of the total vote. That means candidates need a minimum of 35 MPs backing their bid to get on the ballot paper.

The leadership camps are keeping their levels of support private, but it is claimed Burnham and Cooper already have the support of more than 100 MPs. The Kendall camp claim to have the 35 to get on the ballot paper, but Hunt and Mary Creagh, the shadow international international development secretary, are thought to be well short. Hunt, who made no effort to organise prior to the election defeat, is starting from a long way back and has yet to declare he will stand.

One senior Kendall supporter said: “We want as many modernising forces on the ballot paper as possible... We are not just trying to challenge the politics of Gordon Brown and Ed Miliband, we are also challenging their way of doing politics.”

Sheerman, the former chairman of the education select committee and a supporter of David Miliband in 2010, said: “I have been around a long time and I have been picking up how Unite supporters are putting pressure on MPs especially new MPs to support one or other candidate, and telling people if possible let’s keep some candidates below the 35 threshold.

“I have been well-behaved for five years. When David Miliband lost five years ago we were all taken into a darkened room, and told we were to accept the result and told not to criticise Ed Miliband. Well, I have been silent for five years, but we know the reality is had David been chosen in 2010, we would have won the general election. It was a fix by Unite’s merry men in 2010 that stopped David, and we cannot have that again.

“The 2010 result, and the way it happened, means we need a different relationship with the trade unions. We don’t want to break it, but we have to be realistic about the role of unions in society. They are smaller than they ever were and they are increasingly rare in the private sector. They do not provide troops on the ground or at general committees. The number of trades unionists that are active in the Labour party on the ground is tiny.”

Sheerman’s daughter was a special adviser to David Miliband and now works for him in New York.

Len McCluskey, the current Unite general secretary, did not take the helm at the union until after the Labour leadership election in 2010.