In April Lotto revealed the nation's "luckiest" stores. Unichem Stortford Lodge Pharmacy in Hastings came in at No.1 having sold 39 first-division winning tickets.
Manager Nanette Woodham said the outlet had "definitely been busy" this week.
"It's been constant since Monday. I think we're in for a crazy day."
A lot of people were playing who didn't usually, she said.
"It creates a bit of atmosphere, it's such a large sum of money."
In April an Ashburton couple won $22.2 million at Countdown Ashburton.
Checkout manager Chris Hill said they'd sold more than 20 tickets to eager punters before 9am today.
"Sales are high at the moment, our growth has gone up 10 per cent in the last three weeks with each draw."
Mr Hill added that for the first time, Wednesday sales had beaten the previous Saturday's.
In June last year a ticket bought at Springfield Superette and Lotto in Rotorua won $24.3 million.
Shopkeeper Rahul Patil said people had been coming from as far afield as Auckland and Wellington to cash in on the store's lucky reputation.
"We've got people coming to our shop from all over especially to buy tickets here."
Lotto spokeswoman Emilia Mazur said full information on ticket sales would be available once the draw was completed, but she expected to sell more than one million tickets for tonight's jackpot.
Lisa Dudson, financial advisor at Acumen, said the best thing people could do if they won big was "take a deep breath and do nothing".
"People can do crazy things when they win big, when they should give it time to settle.
"It's about thinking. Think about what's important to you. How do you want to add value to your life?"
People often failed to realise that "money didn't necessarily buy happiness", and that was where the aid of a financial advisor or a life coach could prove helpful.
"I would find out about them. What are their dreams and aspirations?"
She believed the right advice was critical.
Winners would be drawn about 8.20pm on TV One. Six Lotto numbers and one bonus number are drawn from a possible 40, and one Powerball number is drawn from a possible 10.
Big winners can claim their prize in person at Lotto's Auckland offices, where champagne on ice is at the ready. A must-be-won draw will be called at $40 million if Lotto's prize money continues to jackpot, so if you're not the lucky winner tonight, you're in with a chance on Saturday.
