David Shearer would have known he was wasting his breath with his last-minute plea to John Key to drop the legislation allowing National to sell minority portions of four state-owned energy companies.

While National might occasionally heed the "voice of the people" - as the Labour leader urged yesterday - the Mixed Ownership Model Bill, which will get its final reading in Parliament this afternoon, will not be such an occasion. National has endured too much pain from its privatisation plans to back off at the point the bill becomes law.

Getting the first share float in Mighty River Power under way has now become a litmus test of National's authority as the governing party.

Moreover, quite apart from the fiscal problems that would arise from the Government abandoning its plans, cancelling the float would also blast a huge hole in National's second-term agenda and be a massive blow to caucus and party morale.


But there is another reason why National will hang in there. With one proviso, the political pummelling it has experienced over the sales programme should ease from here on in.

That proviso is that the Treasury and the financial institution helping it with the float get the price of the shares right.

If the float is under-subscribed, it will be a political disaster with accusations that the price was too high for the so-called"Mum and Dad" investors.

If it is over-subscribed and people cannot get a meaningful quota of shares, the accusation will be that the Government is flogging off assets too cheaply.

The bill's passage through Parliament was always going to be a difficult phase for National. The select committee stage saw submission after submission opposing the measure for myriad reasons.

The wafer-thin majority with which the bill has passed through each parliamentary stage has helped opponents who claim National has no mandate for asset sales.

Bar ministers' question-time, that platform will no longer be available to Opposition parties after today. The arguments both for and against privatisation have anyway been rehearsed and repeated to the point of exhaustion.

The petition seeking a citizens-initiated referendum is unlikely to collect the roughly 305,000 signatures needed to force one before Mighty River Power is floated.

By the time a referendum is held, minority shareholdings of up to 49 per cent may have been completed in two or three of the four companies affected - Mighty River Power, Genesis, Meridian and Solid Energy.

For now, the political debate is in limbo until the fine detail of the first float is unveiled in coming weeks.

At that point, National should be able to go on the front foot and more successfully sell what it sees as the positives of privatisation, while highlighting how it intends stopping such things as foreign ownership with the incentive of a loyalty bonus for those who hang onto their shares rather than trying to make a quick profit.

There is likely to be a slick advertising campaign promoting the float, possibly involving a well-known New Zealander with high credibility - the precedent being former All Black captain Sean Fitzpatrick and the Auckland International Airport float in 1998.

It is unlikely National will change people's minds on privatisation. But a Herald on Sunday poll showing nearly 60 per cent of voters saying they would buy shares in any state-owned asset is good news for National after all the negative publicity.

That result suggests that while opposition to such sell-offs may be widespread, it does not cut deep enough to be politically fatal for the Government promoting them. Add that to the sighs of relief on the Government benches as the legislation is passed this afternoon.