Picking the winner of the Melbourne Cup looks like it could have been too hard for some punters as betting on Australia's greatest horse race dropped this year.

Melbourne Cup turnover across Australia came it at around $148 million.

In NSW and Victoria, betting agency Tabcorp raked in $90.6 million as customers made the agonising decision on which horse to back from one of strongest fields in the race's rich history.

The $90.6 million was down 2 percent on 2012.

A total of $133.7 million was handed over in the two states on the 10-race card at Flemington, down 4.8 per cent on last year.

In Victoria, $34 million was bet through the TAB on the Melbourne Cup while in NSW there was $47.5 million wagered.

One customer scooped a lotto-like dividend, collecting $118,652 from an outlay of just $1 on the Melbourne Cup First Four.

Picking Fiorente, Red Cadeaux. Mount Athos and Simenon in the correct order in NSW returned a little less of $107,190.

Fixed odds betting accounted for $9.1 million across both states, and for the first time there were more than one million tickets sold in a single day.

The winner, the Gai Waterhouse-trained Fiorente, paid $7 on both NSW and Victorian totes.

One punter put $27,500 on Fiorente just before the start of the race and collected $192,500.

It is the first time since 2005 that the favourite has won the Melbourne Cup.

"By the end of the day our wagering system will have processed in the range of 50 million transactions," Tabcorp's David Attenborough said.

Queensland-based Tattsbet reported around $42 million in preliminary Melbourne Cup sales, which includes South Australia, Tasmania and Northern Territory.

Queenslanders bet almost $30 million.

The West Australian TAB drew $15.3 million worth of Melbourne Cup bets, down slightly compared to last year's turnover.

A TAB spokeswoman said the takings were down by 1.96 per cent.