The majority of Labour members and supporters want Gordon Brown to stand down as leader, a survey has found.
The poll for The Independent found that 54% of Labour supporters would prefer someone else to lead them into the next general election.
The results will be a significant blow to the Prime Minister as they represent the views of the Labour grassroots.
More than half of respondents (57%) said there should be a vote at this week's conference on whether Mr Brown should face a leadership election.
Some 45% believed that changing the party's leader before the next election would improve Labour's prospects, while 28% thought it would worsen them.
The poll - conducted by Labourhome.org, an online forum for the Labour grassroots - also rated Mr Brown's personal performance.
Asked to rate Cabinet ministers out of 10, Labour members and supporters gave him an average of 4.3. Only Chief Whip Geoff Hoon and Transport Secretary Ruth Kelly got lower scores. Health Secretary Alan Johnson was given the highest rating (6.2), followed by Environment Secretary Hilary Benn (5.9).
If Mr Brown was forced to stand down, Mr Miliband would be the favoured candidate, with 24.6% of Labour grassroots support.
He is followed by Mr Johnson (18.1%), backbencher Jon Cruddas (11.3%) and Mr Straw (9.6%).
The online survey of 788 Labour members and supporters was conducted by Labourhome.org.
