The first question for voters is, who would get the benefits of increased government spending? Tax cuts for wealthier earners with big mortgages may see money go in one pocket and out the other. Tax cuts for older homeowners with term deposits may not over-stimulate the economy because they are more likely to save their windfalls. Or they may also benefit from higher interest rates on their term deposits. So Key's question about how much a lolly-scramble would put up your mortgage is not that simple.
Not everything is the same in 2014 as it was in 2005. The economy ran about 3 to 4 per cent "hotter" than its potential growth rate between 2005-08, but this time the Reserve Bank says the economy will run about 1.5 and 0.4 per cent hotter over the next three years. The hotter the economy, the higher the OCR's sensitivity to fiscal stimulus.
Back in 2005, household debt was about $115 billion but rising at 16 per cent per annum, suggesting an economy overheating. By election time this year, mortgage debt will be about $205b and growing at about 6 per cent. Term deposits in 2005 were worth just $59b, but are now $125b and rising at 9 per cent, so there would be plenty of voters cheering for higher interest rates.
Perhaps a voter should ask a politician promising more spending or tax cuts: "What type of spending and tax cuts are you planning, and who would get them?" Ultimately, some research into party policies would be better than the assumed answer to a rhetorical question.