The contest between Welsh Secretary Alun Michael and backbencher Rhodri Morgan was sparked by the resignation of the former Welsh secretary Ron Davies after a "moment of madness" on Clapham Common, South London.

The three-month delay is to allow a one-member-one-vote ballot to take place in constituencies throughout Wales, but is thought to favour Mr Michael.

Alun Michael: Leadership's choice

The constituency ballot of party members makes up just one third of the total electoral college.

Another third is made up from the trade unions, with Welsh MPs, Euro-MPs and assembly candidates making up the final third.

Mr Michael is Prime Minister Tony Blair's preferred choice to stand as Labour candidate to become first secretary of Wales.

The current front runner in the party race, Mr Morgan is not seen as a safe pair of hands by Labour bosses.

Westminster insiders point out that despite the Blair government's attempts to distance itself from the unions it will be relying on them to deliver the election for Mr Michael.

Rhodri Morgan: Popular candidate

In the previous contest, in which Mr Davies ran against Mr Morgan, the unions backed the former Welsh secretary by a ratio of nine to one.

Mr Michael responded to the news, saying: "I have made it very clear that I thought it was of paramount importance that all party members be given a vote.

"I also think that the general approach is sensible since the Labour party in Wales is a family in which the trade unions, the Co-operative party and others also have a stake.

"I have said from the beginning that I would accept and abide by any arrangements and requirements decided upon by the Wales Labour party for the conduct of the election and that remains my position."

Earlier this week, Welsh Labour MPs said they wanted the taskforce to select an electoral college allowing constituency parties to ballot all their members.

The contest is set to go ahead despite the hopes of the leadership that Mr Morgan would stand aside and let Mr Michael become Labour's Welsh leader unopposed.