BBC Sports Personality of the Year award nominees due to be announced

Bradley Wiggins wins gold for the men's individual time trial cycling event on day five of the Olympics (Getty Images)

The race for the hotly-contested BBC Sports Personality of the Year award will take shape tonight when the 12 contenders are announced.

The unprecedented success of Britain's sportsmen and women, particularly at the London Olympics and Paralympics, has prompted the BBC to extend this year's shortlist from 10 to 12.

The nominees have been chosen by a panel that included BBC Sport executives, three newspaper sports editors, former nominees Sir Steve Redgrave, Baroness Tanni Grey-Thompson and Denise Lewis, and Baroness Sue Campbell, chair of UK Sport.

In previous years the shortlist had been decided by nominations from sports editors of newspapers and magazines, but there was controversy last year after the final list contained no women.

That is highly unlikely to be the case this year, with Jessica Ennis one of the faces of the Olympics and the first athletics gold medallist for Britain in London.

Swimmer Ellie Simmonds, meanwhile, was a huge star of the Paralympics and Nicola Adams won the first ever Olympic gold medal in women's boxing.

All three face an uphill battle to claim the main prize, though, with cyclist Bradley Wiggins the clear favourite.

The engaging and hugely popular 32-year-old became the first British rider to win the Tour de France this summer before adding Olympic gold in the time trial, his seventh Olympic medal.

Wiggins' biggest rivals for the prize are expected to be tennis player Andy Murray and athlete Mo Farah.

Farah provided two of the biggest moments in the Olympic Stadium with stunning victories in the 10,000 metres and 5,000m, becoming the seventh man to achieve the feat and the first Briton.

Murray also excelled at the Olympics, winning gold in the men's singles and silver in the mixed doubles with Laura Robson before going on to win his first grand slam title at the US Open with a dramatic five-set victory over Novak Djokovic.

Other names expected to be in the frame include cyclist Sir Chris Hoy, who added his fifth and sixth Olympic golds in London, athlete David Weir, a four-time gold medallist at the Paralympics, and golf's world number one Rory McIlroy.

The winner will be announced at a star-studded ceremony on December 16, presented by Sue Barker, Gary Lineker and Clare Balding at London's ExCeL centre in front of an audience of 15,000 people.

The show also gives out awards to the team, coach, overseas and young sports personality of the year plus prizes for unsung hero, lifetime achievement and the Helen Rollason award for outstanding achievement in the face of adversity.

The remaining tickets sold out in less than an hour this week while London 2012 volunteers and young people will share 1,000 free tickets.

PA