The gay marriage debate was set alight by three unlikely heroes - all of them grey-haired, conservative MPs.
Speeches by the National Party's Paul Hutchison, Chris Auchinvole and Maurice Williamson eclipsed efforts by younger, liberal counterparts.
In the first reading in August, Dr Hutchison became the first MP to change his stance on the bill.
He had told the Herald the day before that he would vote against the bill. But after a late-night phone call to the bill's sponsor, Louisa Wall, he changed his mind.
Dr Hutchison told Parliament in his speech: "I have thought long and hard about it, and despite ... many attempts, I simply cannot construct a strong enough intellectual, moral, health, or even spiritual argument against it. Consequently, I will be voting for the bill."
