BBC News Online talks to one of the Mercury Music Prize judges to find out how they go about selecting the winner.
The 10 men and women choosing the recipient of Britain's most influential music award face a barrage of criticism - whoever they pick.
Ms Dynamite showed just how it felt to win last year's prize
The Mercury has established a reputation for championing lesser known artists - but if one should win they are dismissed as "obscure".
The prize extends its reach to cover styles such as classical, folk and jazz - for which it stands accused of "tokenism".
At the same time the shortlists rarely fail to embrace the mainstream - yet major rock acts such as Travis, Coldplay and Radiohead have lost out to rank outsiders.
The inclusion of these bands at all is enough to upset some critics who deride them as predictable choices in little need of exposure.
"Whoever wins you will always get stick," admitted Mercury judge Colin Irwin, who will sit down with nine colleagues on Tuesday night to determine the winner.
Mr Irwin, 49, a former assistant editor of Melody Maker and the panel's folk and roots expert, joins a string of fellow specialists in fields such as dance, classical and jazz.
"There is no pattern. People try and say, 'this is a Mercury record', but it isn't really like that because the judges change each year anyway.
"There's no ground rules. They don't say, 'this year we want an urban record, or a progressive record'.
"Look at this year - The Thrills and The Darkness have both made retro records and both are included. I don't think you can make any hard and fast rules."
Previously, acts as diverse as Talvin Singh, Gomez, Portishead and Badly Drawn Boy have lifted the prize.
This year's list again reflects a vibrant cross-section of styles - from rock giants Coldplay and Radiohead to UK garage newcomer Dizzee Rascal, jazz musician Soweto Kinch and soul duo Floetry.
Although the bookies have their favourites, Mr Irwin insisted the winner was as impossible to predict now as when the prize began 12 years ago.
It can get quite heated - I've never known it come to blows but voices are raised
Colin Irwin, Mercury judge
Judges could argue passionately for their choice, but it relied on support from colleagues to stand a chance.
"As an individual judge you can certainly make a case. For instance, I've championed Eliza Carthy and said people should listen to it, but I couldn't have done it on my own."
Chaired by rock academic Simon Frith, the group is mixed in race, age and gender. It includes Daily Mail journalist Adrian Thrills, composer Kate St John and DJ Gilles Peterson.
They embark on the long process of whittling down upwards of 150 albums from a longlist - to a more manageable 30 or 40, then to the shortlist of 12.
Rock band The Darkness are among this year's favourites to win
Describing the final judging process, Mr Irwin said: "You sit in a room, go around a table and say what you think, which one you like, and gradually knock off albums.
"You are left with three or four who will have their champions, and you just argue - and the arguments can go on a long time.
"It can be pretty vigorous - it's quite animated. It can get quite heated. I've never known it come to blows but voices are raised."
Mr Irwin angrily rejected charges of tokenism in the Mercurys. "It's such a lazy term - a record is there by right," he said.
"Surely we have learned now what is good music and what isn't, and people are opening their ears to certain things - that's partly the beauty of the prize, if it encourages people to listen to different things."
Mr Irwin's personal choice for this year? Dizzee Rascal - "the one that rocked me back on my heels."