Gordon Brown’s leadership team will try to deter any heavy-weight challengers by demonstrating a massive show of support for him on the day that Tony Blair announces he is going, The Times has been told.

As May 8, the day chosen for the restoration of devolved government in Northern Ireland, became Westminster’s latest favoured day for Mr Blair’s resignation timetable statement, Mr Brown’s campaigners said that Labour MPs were queueing up to back him.

At the same time David Miliband, the Environment Secretary, endorsed Mr Brown more strongly than before.

Finally killing off speculation that he might stand, he hailed Mr Brown as an “outstanding Prime Minister in-waiting”. “Anyone planning a secret bid would not have said that in the House of Commons,” a senior backbencher said.

The choice of Jack Straw as Mr Brown’s campaign manager, and Mr Straw’s subsequent signing up of key Blairites such as Andy Burnham and Liam Byrne to help him, is regarded as a coup for Mr Brown.

Yesterday Gareth Thomas, who is one of the organisers of Hilary Benn’s deputy leadership campaign, let it be known that he was backing the Chancellor. He was once parliamentary private secretary to Charles Clarke, who has repeatedly refused to rule out standing for the leadership.

Insiders say that over the coming weeks more and more Labour MPs, including ministers, will go public with their backing for Mr Brown.

Downing Street insiders said that the Brown camp was trying to present the outcome as a foregone conclusion. An insider said: “If Jack produces 200 names saying they support Gordon, there won’t be much point in anyone serious putting their head up.”

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