Is this the woman who will rule Blair's new model Labour Party?

Labour is preparing to break with tradition by appointing a woman as its chief official for the first time in its 100-year history.

Margaret McDonagh, at present general election campaign co-ordinator, is tipped to take over from Tom Sawyer as the next general secretary.

Rumours among Labour ranks suggest Mr Sawyer could be rewarded for his work in modernising the party and in planning the general election campaign with a seat in the House of Lords. If he goes, Ms McDonagh is believed to be foremost among those favoured to succeed him.

A former London organiser for the party in her late thirties, she is seen as tough, ambitious and well-organised. She has impressed senior figures with her work on the campaign, particularly in co-ordinating work in target seats.

Ms McDonagh's sister, Siobhain, is standing for Labour in the key seat of Mitcham and Morden, where Angela Rumbold, a former Conservative minister, had a 1,700-vote majority at the last election.

The post of general secretary is elected and Mr Sawyer, a former union official, was voted in by the party's national executive from a shortlist of four. Ms McDonagh might be favoured by many members of the committee, as the appointment of a woman would be perceived as a modernising message to members.

Colleagues have been generally positive about the suggestion, although a few hinted that they found her efficiency a little frightening.

"She's very capable, she's quite steely and she runs a very tight ship," said one. Another commented: "I would always make sure I was on Margaret McDonagh's side. I would feel I had failed miserably in life if I was anywhere but right behind her."

Ms McDonagh, a Blair loyalist, was recently drafted in to help deliver a "charm school" to party candidates, coaching them through general election tactics and making sure they were well aware of the campaign message.

She was also reported to be the author of a blunt internal report which warned that Labour was vulnerable on the economy and immigration. "A problem for Labour is that of trust. This is Tony Blair's weakest rating," it said.

Labour may need to create a large number of new life peers in to push through its constitutional reforms, and the leadership is looking for capable, hard-working candidates who will treat their posts as full-time jobs rather than as straightforward honours.

Mr Sawyer has been general secretary since October, 1994 and a key figure in preparing for the general election. He is in charge of the "Party into Power" initiative which is planning reforms to the party's structure.

Ms McDonagh could not be contacted for comment last night.