A crowd of more than 34,000 is expected at Moonee Valley to see Winx attempt a record-equalling third Cox Plate.

Winx will join Kingston Town, successful in the 1980/81/82 Cox Plates, if she wins the 2040m $3 million race on Saturday.

Moonee Valley Racing Club chief executive Michael Browell says the club has been overwhelmed by the support of the public wanting to see history.

"We saw it when Black Caviar had her last run under lights here in Victoria but to see it here for the Cox Plate from people around the country and around the world has resulted in people missing out on tickets," Browell said.

"It's extraordinary in this day and age to get a crowd like this."

Browell said he had seen pictures from old Cox Plate meetings where crowds may have been bigger, but marquees in the centre of the course result in a reduced capacity.

The tighter confines of Moonee Valley provide for an electric atmosphere both before and following the Cox Plate.

"Every seat in the grandstand was sold out in four days of the tickets going on sale," Browell said.

"So the crowd will be enormous right on top of the track and the atmosphere will be electric.

"The roar will be like a soundwave if Winx hits the front at the top of the straight which will then carry all the way down the straight."

The final general admission tickets were sold out earlier in the week.

Winx is the $1.15 favourite with TAB.