"If you went to New Zealanders and said, 'would you like to borrow another $7 billion in the world's markets where debt is a major issue, and that's what has dragged down Italy, and Greece, and Ireland, and Portugal and Spain, or would you like to build no new infrastructure at all for the next five years and pretend we're going to be a growth economy, or would you like to have the Air New Zealand model operating in a few more companies' I think you'd get a different answer."
When asked what National would do in the future if New Zealand was in economic trouble and had already partially sold assets, Mr Key said it was a "nonsense argument".
"Come back and ask me 2014," he said.
"The answer is get your books back in surplus by 2014."
Mr Key expected a close election, despite Labour's poor showing in the polls.
"It's not just Labour, it's Labour with the Greens, with New Zealand First, with the Mana Party."
"Think about that for a minute.
"We've got a global financial crisis, we've got a huge amount of debt. What do those four parties want to do? For a start off, they want to spend money we don't have. So they are a cocktail for borrowing, that's for sure."
Mr Key said those parties were "volatile", and the country needs a stable government.
He said while National and the Maori Party disagreed on a lot of policy, they had showed they could work together.
Mr Key believed MMP would win the referendum, although Mr Key said he would be voting for the supplementary member system.
He reiterated he believed his conversation with the Act Party's Epsom candidate John Banks was deliberately taped, despite cameraman Bradley Ambrose tomorrow seeking to have the High Court at Auckland deem the conversation public.
Mr Key would not comment on whether he would have some explaining to do should the conversation be deemed public, as the case is before the Court, however he doubted that the next week would again be dominated by questions about the tape should that happen.
Asked when he was last frightened, Mr Key said "it happens on a daily basis".
"It's called picking up the Herald."