It's anyone's guess who will take home the 2008 Scotiabank Giller Prize.

But if the last three years are any indication, the voters in the Guess the Giller contest may already have a pretty good idea.

The contest, which allows reading aficionados to cast their choice for Canada's top literary honour either online at www.guessthegiller.ca or through their local library, has accurately predicted the results in advance of the November gala since 2005.

Mary Swan's "The Boys in The Trees" is currently No. 1 in the ranking. The other finalists include Joseph Boyden's "Through Black Spruce," Anthony De Sa's "Barnacle Love," Marina Endicott's "Good to a Fault" and Rawi Hage's "Cockroach."

Guess the Giller started with the Toronto Public Library in 2003 and has now expanded to more than 30 public library systems across the country that provide either online access to the contest website or traditional ballot boxes in more rural areas.

The contest was meant to encourage interest from everyday readers and not just those in literary circles.

"What our intent was was to bring the books and the excitement of reading the books and trying to select the winner to a wider audience through the public library system in Canada," says Elana Rabinovitch, administrator for the Scotiabank Giller Prize and daughter of founder Jack Rabinovitch.

In the first three weeks of this year's contest, more than 5,000 entries have already been received.

As well as bragging rights, one lucky reader who chooses the correct winner will win the Grand Prize of a trip for two to one of Canada's literary festivals and a set of the autographed shortlisted books. Secondary prizes include 1 of 60 sets of autographed shortlisted books or 1 of 10 $50 gift cards from Chapters/Indigo.

Rabinovitch says not only does the contest encourage people to read the Giller finalists, the contest has helped create a book club culture.

"Typically with book clubs there's always a discussion about how you go about picking books and whose turn it is to pick a book and this is a ready-made book circle or book club selection," says Rabinovitch.

It also helps to create a buzz around Canadian authors, she says.

Up-to-date results on who's ahead in the running can be found on the Guess the Giller website.

The contest closes Nov. 10.