"I dedicate this race today to Frank and his wife Mercedes and their three little girls," she said.
"They have a little girl my daughter's age, so it really hit me hard."
"I know he was watching and cheering me on the whole time, this was for Frank, I feel like I had an angel on my side."
Following behind McCauley came Kiwi athlete Teresa Adam and Meredith Kessler.
Adam said she was "thrilled" to take out silver - especially after receiving a five-minute stand-down penalty for littering while on the bike course.
"I had some bad luck and a bit of a mistake on the bike," she said.
"As well as physical it is emotional too, I had a five-minute penalty and I was sitting on the side of the road and thinking 'there goes the race' but I stuck to my race plan and managed to get on the podium, so I am pleased."
American national Meredith Kessler came in third - a result she said she was "stoked" with, a little more than a year after giving birth to her son Mak.
Kessler had won the contest five times before this one.
Hours after the podium finishers crossed the line, hundreds of Ironman competitors would continue running - aiming to make it to the finish line at the Northern Domain in Taupo before midnight.
