LAING O'Rourke is on course to build the biggest secondary school in Europe.
The £34 million city academy in Peterborough, known as the Thomas Deacon Academy, will specialise in maths and science.
Drawn up by Swiss Re building designer Fosters & Partners, the school will consist of two buildings meandering along a central concourse, covering 18,200 sq m across three levels.
Three other firms had been in the running for the contract. Sir Robert McAlpine dropped out after deciding it was not worth bidding. That left Taylor Woodrow and Mace to fight it out with Laing O'Rourke.
The battle is now thought to be over, with O'Rourke expected to take first prize.
A source at a rival bidder said: 'The race looks like it is run but you never know with these things.At the moment Laing O'Rourke is a mile ahead but just in case they fall the rest have got to keep on running.
'In other words nothing is official but the client has clearly lined up its winner. It's a case of filling in the blanks and making sure everything is satisfactory.
Until that is done there is at least a possibility.'
The school will provide teaching accommodation for 2,220 students from the age of 11 to 19.There will be extensive sports fields, including a floodlit all-weather pitch, four rugby pitches, three cricket pitches and tennis courts.
The academy will include six colleges in total, aimed at providing a campus environment with lessons replaced by lectures, seminars and tutorials.
The development is part of the Government's target to build 200 city academies by 2010. Following two years of planning the Government agreed to fund the academy, which will also receive funding from the Deacon's School Trust. Local company Perkins Engines, part of US plant giant Caterpillar, will add further cash.
Work is due to start on site in September and the complex will open for the start of the new academic year in 2007.