Man Booker: Jim Crace's Harvest favourite to reap prize

On the shortlist: (clockwise from top left): Colm Toibin, Eleanor Catton, Ruth Ozeki, Jim Crace, NoViolet Bulawayo, Jhumpa Lahiri

The winner of this year's Man Booker Prize will be announced later, with Jim Crace's Harvest the favourite with bookmakers to reap the £50,000 award.

Crace, who has said Harvest is likely to be his last novel, is at 67 the oldest author on the shortlist of six.

Eleanor Catton, 28, the youngest to make the cut with her book The Luminaries, is his closest rival in the betting.

The winner will be revealed on Tuesday night at London's Guildhall.

The prize will be presented this year by the Duchess of Cornwall.

The other authors on the shortlist are NoViolet Bulawayo, for We Need New Names; Jhumpa Lahiri, for The Lowland; Ruth Ozeki, for A Tale for the Time Being; and Colm Toibin, for The Testament of Mary.

Both William Hill and Paddy Power have Crace as favourite at 5/4 with Ladbrokes giving him 6/4.

William Hill said a late surge of support for Eleanor Catton, including a number of three-figure bets, made her 11/4 second favourite, while Colm Toibin was 4/1 third favourite.

"As far as our literary punters are concerned, this year's Man Booker is a three-horse race," said Hill's spokesman Graham Sharpe. "So we will be celebrating if any of the other three runners can win."

Ladbrokes said Catton, at 11/4, had been the best-backed author over the weekend, and could make a late bid for the top spot.

Paddy Power said Catton's odds had been chopped from 9/2 to 3/1.

This year's shortlist, announced last month, features six writers of different nationalities - from Canada, Britain, Ireland, New Zealand and, for the first time in the prize's history, Zimbabwe.

Robert Macfarlane, chair of the judges, said the shortlist was "instantly striking" because of its "global range".

"This is a shortlist that crosses continents, that joins countries and that spans centuries," Macfarlane added. "These novels are all about the strange ways in which people are brought together and the painful ways in which they are held apart."

A week after the shortlist was announced, the Man Booker organisers announced that authors writing in English from all corners of the globe would be eligible for the prize from 2014.

The decision has split the literary establishment.

Some welcomed the expansion of the field, while others said American novelists would come to dominate the prize, which is currently awarded to English-language authors from the Commonwealth, including the UK, Ireland and Zimbabwe.

On this year's shortlist, NoViolet Bulawayo's We Need New Names is about a Zimbabwean girl coming of age in the US, while Lahiri's The Lowland tells the story of two brothers, Subhash and Udayan, brought up in Calcutta in the late 1960s.

Ruth Ozeki's A Tale For The Time Being tells the story of a diary washed ashore inside a Hello Kitty lunchbox and the profound effect it has on the woman who discovers it.

Catton's The Luminaries is a ghostly tale set in Victorian New Zealand. If Catton wins, she would be the youngest ever recipient - she recently turned 28. Her book - the longest on the shortlist at 832 pages - is her second novel.

Ben Okri was the youngest winner in 1991 at the age of 32.

Crace was previously shortlisted in 1997 for Quarantine, while Toibin has appeared twice before - for The Blackwater Lightship in 1999 and in 2004 with The Master.

Toibin's The Testament of Mary is about the mother of Jesus grieving angrily years after her son's crucifixion. At a little over 100 pages, it would be the shortest novel to win the Booker.

Crace's Harvest is an allegorical tale of rural isolation in which the narrator Walter Thirsk sees his village fall apart over the course of seven days.

The six shortlisted writers are each awarded £2,500 and presented with a hand-bound edition of their book. The winner will receive a further £50,000.

This year marks the 45th year of the prize, which was won last year by Hilary Mantel for Bring Up the Bodies, making her the first woman and first Briton to win the coveted award twice.

The winner of the Man Booker Prize will be announced live on the BBC News Channel from 21:30 BST on Tuesday, 15 October.