Internet-Mana will encourage those yet to get on the electoral roll to not only register but also cast their vote at the same time. That meant having volunteer and communications systems working on voter turnout for 18 days rather than just one day.
"In a sense, if you've got the organisation for it you're multiplying your volunteer resources by 18 if you're mobilised on every day rather than just one day."
That meant the election itself would effectively begin on September 3.
National Party campaign chairman Steven Joyce agreed that date now marked the beginning of the election and says his party is also gearing up to fight it on that basis.
The expected increase in advance votes was "definitely a factor in our decision making around campaigning and our advertising".
In recent elections National has polled anywhere between two and four percentage points higher through advance votes than it has on election day. Labour and the Greens have consistently polled lower in advance votes than those cast on election day.
Ms Harre puts National's record in capturing advance votes down to the fact they have traditionally been cast in institutions such as hospitals and rest homes, "so they would tend to reflect more conservative voting patterns".
That theory appears to be supported by the fact NZ First also does better proportionately from advance votes.