"It's not really possible [to estimate] because you have to know the odds of all the horses. It's not liking tossing a coin where you know that there is a half and half chance of head and tails, the probability of having a particular horse winning varies and can't accurately be estimated."
Tom Waterhouse spokesman Andrew Brown said statistics were not deterring punters and the prize was proving a popular drawcard.
"It's an Australian racing first to have an amount that big. The response has been really encouraging."
There were also some caveats around the punt, including that it only stood if at least 20 of the 24 potential horses ran, and the prize was to be shared among all who chose the winning line-up.
In New Zealand, it is standard betting for the race through the TAB. However, its futures book - which allows punters to bet ahead of the final draw announcement - has been popular.
The Victoria Racing Club Spring Carnival started on Saturday with the Victoria Derby Day, featuring the Victoria Derby, Mackinnon Stakes and Lexus Stakes.
The racing carnival ends on Saturday.
Kiwi's outfit takes second in Melbourne
A New Zealand fashion designer picked up the runner-up prize at the Melbourne Cup Fashions on the Field yesterday.
Reigning 2014 Viva Prix de Fashion winner Olivia Moor was wearing a classic Derby black and white ensemble featuring a slim, black, lattice-weave pencil skirt and white silk blouse with a flowing scarf detail crowned with a dome-shape woven leather hat.
She was wearing the same outfit when she won New Zealand's Prix de Fashion.
As part of the prize package, Moor was given entry into the Flemington Oaks Day competition.
Viva Prix de Fashion is New Zealand's premiere racing fashion event and the culmination of Fashion in the Field competitions held at thoroughbred racing clubs across the country.
Meanwhile, despite being some 2600km from Flemington Racecourse, Ellerslie is hosting its own racing event tomorrow featuring 10 thoroughbred races that can be enjoyed from a range of hospitality options.
A fashion competition will seek out the best-dressed man and woman at the event, with a $2000 prize package.
Auckland stylist Michiko Hylands, who will co-judge the Sofitel Luxury Hotels Melbourne Cup Style Award, said she would be looking for statement head pieces and well-put together looks that "up the glam factor".
Q&A Cup fashion
What's in this season?
The main thing is big and bold. Strong bold patterns and striking patterns.
What about headwear?
Structured hats are in. Raceday headwear is getting more extravagant, with fascinators appearing bigger, bolder and more sculpted.
What about the men?
Take a leaf out of Jay Gatsby's book with tailored suits and bold colour combos. And make sure your beard is well groomed.
What shouldn't you do?
Dress in unflattering outfits - and have too much to drink.
