By Justin Parkinson
BBC News politics reporter
Labour chairman Hazel Blears will announce "soon" whether she intends to stand for the party's deputy leadership, the BBC has learned.
Ms Blears has urged Labour to keep its 'sense of unity'
A source said there had been a "strong" show of support from MPs and party members, urging her to launch a bid.
Ms Blears is set to give a speech on Friday warning Labour not to take a "lurch to the left".
So far five MPs, including three Cabinet ministers, have said they will stand for the deputy leadership.
The source said: "Hazel's had a lot of people coming up and saying she should stand, both from MPs and members of constituency associations.
"She will be making her intentions clear one way or another soon, but not this week."
The source said the deputy leadership contest would eventually boil down to three or four candidates.
Some of the declared runners had gained too much exposure too early, while "a lot of people are keeping their powder dry, waiting to see what the field will be".
The deputy leadership contest will take place later this year when John Prescott stands down, at the same time as Prime Minister Tony Blair.
Many commentators think this will happen soon after the local, Welsh and Scottish elections in May.
Cabinet ministers Hilary Benn, Peter Hain and Alan Johnson have already said they will run for the deputy leadership, as have Constitutional Affairs Minister Harriet Harman and backbencher Jon Cruddas.
Chancellor Gordon Brown is seen as the strong favourite to replace Mr Blair, but the deputy contest is regarded as far more open.
Ms Blears, Labour chairman since last May and considered a loyal Blairite, will address Labour's national youth forum in Glasgow on Friday, calling on the party to "reach out" to young voters.
She will add: "We won their support because of New Labour - a modern Labour Party in touch, on their side, and led by a Leader who they knew shared their instincts and aspirations.
"The idea that we win a fourth term by distancing ourselves from that leadership or by dismissing our own successes is dangerously misguided."
Ms Blears will also say: "And if we made the mistake of a lurch to the left, the result would be David Cameron."
At last autumn's Labour conference, she called on the party to maintain its "sense of unity".
She has faced criticism from potential rivals for the deputy leadership that she has been campaigning behind the scenes for some months, according to press reports.