"There always seems to be another big winner popping up," she said.
"It's really exciting being part of such a big draw - every time I sell a ticket I think 'that could be the next big Powerball winner'.
"The store has been packed and customers are buzzing - there's definitely a lot of excitement."
The country's second luckiest spot is Christchurch, which has had 15 First Division wins so far this year.
Coming in near the bottom of the list, in 12th position, Ashburton may not have sold the most First Division winning tickets this year - but it has sold the biggest.
An Ashburton family won $22.2 million with Powerball in April - one of the 10 largest Powerball prizes won in New Zealand history and the second-largest prize ever won in the South Island.
Lotto spokeswoman Emilia Mazur said eight players had won big with Powerball this year - four from the North Island and four from the South Island, with two of those players buying their tickets online.
"It's been an amazing experience changing the lives of these eight Kiwis. We can't wait to see what happens in the draw tonight."
NZ's luckiest Lotto spots
1. Manukau, Auckland - 19 First Division tickets worth $5,589,124
2. Christchurch City - 15 First Division tickets worth $5,566,666
3. Auckland City - 12 First Division tickets worth $6,466,666