The final $1 million had to be raised by the end of October to ensure the project would proceed, however.
Mr Ayton said the foundation would be publicising its "final countdown" extensively over the two-month period, with significant advertising space donated by APN, publishers of the Northern Advocate and the Northland Age, and MediaWorks Radio.
For those who wish to give $1000 or more there is the option of the BNZ "Buy a Brick" initiative, that enables donors to sponsor bricks that will bear their names on a plaque, and will be used to build a wall at the unit's entrance.
Those wanting to buy a brick should inquire at any BNZ branch or Business Partners Centre. Smaller cash donations may be made at any BNZ branch or via the Project Promise donation boxes in shops and public places across Northland.
Donations may also be made online by internet banking direct credit, or through the Givealittle.co.nz charitable donation website.
The foundation will also be publicising the ability to donate to the project via bequests, an important potential funding source that Mr Ayton said had not yet been "fully communicated".
"This is where donors commit to making a gift to Project Promise in their will, and the money counts towards the final total raised," he said.
Cautious optimism
Of the $2,013,333 raised by Project Promise so far, $529,821 had come from fundraising events and activities, $856,581 from general donations, $41,343 from collection boxes, and $309,000 from the BNZ "Buy a Brick" initiative. The balance had been raised by Lions clubs and Freemasons.
Mr Ayton was "cautiously optimistic" that the final $1 million could be raised in the short time-span.
"We'll need everyone's support for this final countdown, but the people of Northland have been hugely generous so far, and we know there is significant support for this project," he said.
"We're already two-thirds of the way there, and our job during this final push is to get people who've been meaning to donate to actually do so. If you've been thinking about donating, then please, now is the hour. We're not going to get there without your help."
The planned centre will provide day-stay treatment for cancer patients, including initial consultations, chemotherapy treatments and follow-up from a team of medical experts including other related nursing and support services.
Adults who need radiation treatment and those with complex cases requiring specialist care will still need to travel to Auckland, and children may still receive some of their treatment at Starship Children's Hospital, which has a specialised child cancer unit.
Assuming the project can proceed, tender documents for the construction will be issued by November 1.
"As promised all the way through this campaign, and within the constraints of the tender process, we're aiming for as much of the new cancer treatment centre as possible to be built by local businesses and suppliers," Mr Ayton said.
For more information about Project Promise go to www.northlandcommunityfoundation.org.nz or www.facebook.com/ProjectPromiseNorthland.