John Healey, the former Labour housing minister and shadow health secretary, has announced he is running to be deputy leader of the party.
He is a late entrant to the race, becoming the seventh candidate for the position, and has already backed Yvette Cooper for the position of Labour leader.
Healey, MP for Wentworth and Dearne, said he had not originally intended to stand but was "dismayed at how narrow and shallow the debate has been so far".
As he announced his intention to stand, Healey wrote in the Guardian:
I know I'm a late entrant when others have been up and running for some time. But the scale of the defeat, the complexity of the lessons and the huge task of holding things together while we rebuild requires a unifier - someone who can work across the political breadth of the party and with the unions.
Our new leader must be able to give their total attention to establishing themselves and re-establishing Labour with the country. Labour's internal affairs have to be left largely to others, but their deputy must be much more than a party manager and motivator.
He has previously spent four years at the Treasury when Gordon Brown was prime minister, and has also held positions as housing minister and Ed Miliband's shadow health secretary.
He said he was confident of gaining enough support, despite the number of candidates. Other candidates for the role are Rushanara Ali, Ben Bradshaw, Angela Eagle, Stella Creasy, Caroline Flint and Tom Watson.
To be on the ballot each candidate needs nominations from 35 MPs. However, with only 232 Labour MPs, two of those standing are unlikely to gain enough support to make the ballot paper.