Such mass support will likely put pressure on any other contenders who need 44 nominations to battle for leadership against Mr Brown.
Currently only two MPs, the left-inclined Michael Meacher and John McDonnell, have declared they will run for the party's leadership when prime minister Tony Blair steps down after a decade in charge.
It is thought that Mr Brown's team is working on the premise that Mr Blair will step down on May 9th with his successor stepping into the job on May 15th.
The Guardian newspaper also reports that the canvassing of MPs was hoped to stop any last-minute bids by staunch Blairites.
Charles Clarke, the home secretary John Reid and David Miliband are expected to be the three names put forward if the local elections on May 3rd do not go to plan.
However last month foreign secretary Margaret Beckett publicly warned Mr Miliband not to run for Labour leadership, telling the Daily Telegraph that the environment, food and rural affairs secretary would be "daft" to run when bookie's favourite Mr Brown was "head and shoulders" above the handful of others who have announced they will run for the leadership.
Mr Miliband has since ruled himself out of running, saying he would not be "seduced" by his supporters.
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