A few months ago, Lord Drayson was sitting through speeches in the House of Lords, daydreaming of hurtling round a racetrack. But unlike most ordinary men approaching their midlife crisis the minister for defence equipment and support, as he then was, had £80m burning a hole in his pocket. In November last year he decided it was time finally to swap his ermine for a fire-retardant race suit.

Last weekend The Sunday Times joined him in the pits at the Sebring race circuit in Florida for his first race in the American Le Mans endurance series. If he performed well it could be his entry ticket to the Le Mans 24 Hours in France in 2009 and the fulfilment of a dream. “It was a now-or-never opportunity and I just feel so privileged to be here pursuing something I’ve wanted do since I was a child,” Paul Drayson says – the “Lord” bit was added when he became Baron Drayson of Kensington, a Labour life peer, in 2004.

Drayson grew up within earshot of the Brands Hatch motor racing circuit but never thought he would be able to follow in the tyre tracks of his heroes Graham Hill and Jackie Stewart. But when he sold his pharmaceuticals business, Powderject, in 2003 for £542m, he netted himself a multi-million-pound fortune and decided to splash out on a few track days. Then 43, he moved in quick succession from that to racing classic cars and on to the British GT championship, funding it all from his own pocket. His new-found career as a government minister – he joined the government in 2005 – meant he couldn’t accept sponsorship.

In Florida, Drayson has put a safe distance between himself and political commentators who demanded to know the real reason he had stepped aside from government. Had it anything to do with plans to cut his department’s spending? Was it a private protest against the lack of equipment for the armed forces? Or perhaps a delayed reaction to the row over Drayson’s £500,000 donation to the Labour party that critics speculated had paid for his ennoblement?

None of those, Drayson insists. His decision had nothing to do with politics and everything to do with his passion for motor sport.

The Sebring 12-hour is the first race in the American Le Mans series, which is a tried and tested route to qualification for Le Mans proper, the world’s most famous endurance race.

Drayson is joined by Jonny Cocker and Tim Sugden, his co-drivers in the Drayson-Barwell team. They will take it in turns behind the wheel of the Aston Martin DBRS9 GT3 (a racing version of the DB9). Drayson is first, with a 40min stint, followed by Cocker, who will drive for an hour, then Sugden for another hour, and so on in the same order until the finish 12 hours later.

Before Sebring the longest race the DBRS9 had completed was two hours. Next month the car will be replaced by an Aston Martin Vantage GT2, better suited to endurance racing. Until then Drayson’s team is going to struggle to keep up with the pace. “This is basically a sprint car, and we’re asking it to take part in a marathon,” one of the pit crew says.

Two and a half hours into the race, the car is performing well. The team are 10th in their class of 16 cars – ahead of expectations. The car comes in for a pit stop as Drayson psychs himself up for his second drive. In just a few seconds four new tyres are in place; the refuellers step aside, having pumped 100 litres of bioethanol into the car’s twin tanks (Drayson’s car is the first in the Le Mans series to run on biofuel).

Drayson sprints round to the driver’s door, helps Sugden untangle himself from the seat restraints and eases his small frame into the seat. A cool box, used to pump cold water around a body suit worn by Drayson, is secured into place. With no air-conditioning in the car, the cool suit is vital to stop the drivers passing out from heat exhaustion. As the tyre-changers step back, Drayson gives the thumbs-up and floors the accelerator, roaring out of the pit lane. Things are looking good. Even finishing the race in such an unsuitable car, without the level of experience of many of their competitors, would be an achievement for his team.

Then comes Drayson’s crash. One moment he is hurtling gloriously around the track in the third hour of the 12-hour race; then suddenly, less than a minute after leaving the pit lane, he misjudges a corner and skids into the concrete safety wall at 120mph. Chunks of the Aston’s green carbon fibre body go flying as the car slams, rear first, into the barrier.

He calls it in over the team radio and for a brief moment the pit crew are silent. Elspeth, Drayson’s wife, who wears the same flame-retardant overalls as the pit crew, with her name embroidered onto the belt, waits anxiously for further news. She scans the TV monitors but they don’t show the crash, concentrating on the race leaders. “This is always the worst part,” she says. “But, thank God, Paul is okay.”

Behind her, slumped against a wall, Sugden looks utterly drained after his drive. He empties two bottles of water over his face but it still glows red from the exertion. Hearing that Drayson has crashed on the team’s 65th lap he drags himself up from the floor.

In the two minutes before Drayson coaxes the damaged car back to the pits, little is said. The rules of the American Le Mans series allow almost every part of the vehicle to be changed during the race except the transmission, chassis and engine. But as the car is protected by only a flimsy carbon fibre shell, the chances of serious damage are high.

Deep gouges in the green bodywork show where the car struck the barriers. Giant chunks of the rear panel have been torn away, exposing the gearbox. One of the twin exhaust pipes has been crushed. Inside, Drayson sits staring ahead, his hands gripping the steering wheel.

The shattered side and back panels are hastily repaired with a roll of black duct tape. But as the minutes tick by, it becomes obvious that the car won’t make it back onto the track. The team can’t risk restarting the engine, which could cause further damage, so the 1,300kg car has to be pushed back to the workshop. As the smashed-up Aston passes a group of bare-chested spectators clutching bottles of beer, one shouts out: “There goes James Bond.” The attempt at humour is lost on the crew. Back at the trailer Drayson disappears into the crew room. His face is a picture of utter dejection. But later that evening, like a true politician, he has managed to put a more positive spin on the incident. “I made a mistake and, as I was told, make a mistake at Sebring and the circuit bites back.

“Nevertheless it’s been an excellent week.” This time his failure to finish won’t affect his chances of a place in Le Mans. But he can’t afford many more mistakes such as this one.

The next race is the St Petersburg grand prix in Florida, on April 5.

What it costs to live like the racing lord

AMOUNT AVAILABLE: £80m
Drayson’s estimated personal fortune after selling Powderject, his pharmaceuticals company, in 2003

DONATIONS: £5.5m
To the Labour party: £1m (approximate total to date)
To charity: £4.5m

RACING: £1,985,000
Aston Martin DBRS9 GT3 race car: £275,000
One season’s British GT car racing: £300,000
One season’s American Le Mans series racing: £1.2m
Repairs after last weekend’s crash: £10,000
Aston Martin Vantage GT2 race car: £200,000

ROAD CARS: £280,000
Aston Martin Vanquish for him: £170,000
Aston Martin DB9 for his wife: £110,000

HOMES: £15.75m
Nether Lypiatt Manor (previously Princess Michael of Kent’s Cotswolds mansion): £5.75m
Town house in Kensington: £3m
Holiday chateau on the French Riviera: £7m

TOTAL COSTS TO DATE: £23.5m
AMOUNT REMAINING: £56.5m

All figures are approximate

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