Up and up - jackpot rises to record $35m

1.5 million Kiwis are expected to be clutching their tickets in the hope of becoming a Big Wednesday winner tonight. Photo / Herald file

A stampede for tickets has pushed the largest Big Wednesday jackpot to $35 million, and the total could grow further today.

Tonight's must-win draw was increased by $5 million in cash and prizes as the Lotteries Commission expected 1.5 million Kiwis to buy more than 3 million Lotto tickets.

Commission spokeswoman Karen Jones said the $35 million pot was based on estimated ticket sales, and there was a chance the prize pool could grow again.

However, at least one mathematician is not lining up to buy tickets.

Imagine a stretch of road one metre wide and 50 metres long. Carpet it with sewing needles measuring 2cm by 1mm and get someone to nominate one needle. Your chance of picking out the same one is about the same as winning Big Wednesday, said Dr Philip Sharp, associate head of Auckland University's department of mathematics.

The odds of a single person winning first division this week are one in 2.72 million for a six-line lucky dip ticket.

"That's why I never buy a Lotto ticket. The chances of my winning are pretty small," said Dr Sharp.

The large number of tickets bought do not change the odds but it increases the chance of the jackpot being won, he said.

After 21 weeks, the Big Wednesday jackpot has reached the $30 million threshold set out in the New Zealand Lotteries' game rules which means it must be won. The prize pool can go higher than the threshold - as it has for this week's competition - depending on the total sales for the draw.

If no one wins tonight's first division draw, the prize will be split and added to the winnings of the next highest prize division in which there are winners.

The luxury prize line-up of cars, travel and a boat can be taken as cash, which means the prize pool can be split evenly if the jackpot is not won.

In last week's draw 465 people won a share of the third division prize. If that happens tonight each third division winner would walk away with more than $75,000.

The largest lottery prize won in New Zealand was a $19 million Powerball jackpot scooped by a New Plymouth player in April last year.

- ADDITIONAL REPORTING: Isaac Davison