Payne won the Melbourne Cup on a $101 chance and English horse Kaspersky is at $81 in the field of nine.
"I don't know if I would be the most popular person in Australia if we happened to beat Winx," Payne said.
"But I don't know whether we have to worry too much about that.
"You can only do your best. We'll go out there and treat it like any other race and give it our best shot and see what happens. It would be pretty special [to win].
"It's right up there with the Melbourne Cup. Obviously it's such a unique race because the committee only let in certain horses that they think are eligible to compete in it. That's, I think, very special because I don't know whether there's too many races in the world that have that.
"If we were able to be successful it would be an unbelievable dream. But just to be out there is going to be great."
Payne also holds a trainers' licence in Victoria and has scarcely ridden in races this season.
She rode her first winner for 2017/18 at Stawell on Monday on a horse she also trains, wearing the same colours Kaspersky carries.
Illness forced her to miss riding Kaspersky when he ran 16th in the Toorak Handicap, but she rode him at trackwork at Moonee Valley on Tuesday and said the horse was in great order.
Payne's brother Patrick won the 2002 Cox Plate on champion Northerly. "I actually took the day off racing in the country that day because I didn't want to miss watching Patrick on Northerly," Payne said. "It was a very special day and something we've always remembered."