Conservative Party leader Colin Craig has reached into his deep pockets and poured $135,000 more of his private wealth into his party's war-chest.
Electoral Commission records show the millionaire property manager and politician made a $45,000 donation to the Conservatives last week, on top of earlier donations of $30,000 in December, $10,000 in November and $50,000 in October.
Mr Craig said he expected the party to spend at least a further $1 million in campaigning for the general election this year and he would pay half of that amount out of his own wallet.
"I would expect to be the major funder of the party for this year and this election. Obviously it's going to gear up as the year goes along."
Mr Craig said some party members had pledged to cover the cost of the $45,000 donation, which was used for a billboard campaign. The remainder of the money was spent on the party's new staff.
Mr Craig has become wealthy through property management, owning companies which manage high-rise apartment blocks.
The Conservatives spent $1.8 million at the previous election - more than any other party except National - but failed to win a seat or reach the 5 per cent threshold.
Mr Craig loaned the party $1.6 million but later wrote it off as a donation.
He said he expected the party to spend less this year because it now had up to 6000 volunteers. He also expected some large donations from individuals, such as the $100,000 it received in May from Hamilton couple Laurence and Katrina Day.
The Conservatives would not be the only minor party with a wealthy backer at this election. The new Internet Party would be bankrolled by millionaire entrepreneur Kim Dotcom.
But Mr Craig believed that the advantage of a wealthy donor only went so far.
"It doesn't give us an advantage over National and Labour, because they use taxpayer money and give themselves $1 million-plus each."
He added: "I think the concept that you can buy an election is nonsense, in terms of the money you spend.
"I think Dotcom could throw the limit at this election and it wouldn't make a scrap of difference."
Donations of more than $30,000 or multiple donations adding up to $30,000 over a year must be declared to the Electoral Commission within 10 days.
All party donations of more than $15,000 must be disclosed.
Last year, the National Party received a $49,220 donation, in four instalments, from Contue Jinwan Enterprise Group, owned by wealthy Chinese couple Susan Chou and Zhaowu Shen. The pair have previously donated $200,000 to the party.
National also received a separate $42,000 donation in July.
In May, Labour received a bequest totalling $430,259 from the estate of Brian James Dalley.