John Armstrong: Arm-wrestle forces voters to take sides

Often prone to exaggeration, Act's weekly newsletter was not far off the mark in billing tomorrow night's leaders debate on TV3 as absolutely crucial for the minor parties.

For those making the cut - Peter Dunne and Jim Anderton have been culled for reasons of time and space - the hour-long debate offers a way into an election from which they feel excluded.

However much they disagree on most things, the minor parties agree on one thing: they are battling a first-past-the-post mentality.

The conventional wisdom is that backing for the minor parties would increase as they got more exposure and the combined support for Labour and National of 80 per cent-plus would dwindle.

On the form of the last two MMP elections, however, the minor parties should have been on the rise before now. Instead, their share of the potential vote is falling, thanks to a sharp drop by NZ First and the slow decline of the Greens.

A rolling average of all polls has the minor parties now currently in Parliament registering about 18 per cent. However, last weekend's One News-Colmar Brunton poll had them collectively rating as low as 12 per cent. That is long way off the 33 per cent they recorded at the last election.

It is not surprising, then, that tomorrow's leaders debate is seen as a chance to break the downward spiral. The unwritten rule of these gladiatorial contests is that there be a winner - and being deemed the winner can transform a party's campaign overnight, as Dunne demonstrated in 2002.

However, United Future's subsequent success at the ballot box also had a lot to do with a faltering National Party leaving a vacuum on the centre-right for someone to fill.

This time the distinct possibility of a National-led Government means National supporters do not have to contemplate voting for United Future as a second-best option for keeping Labour under control.

National's resurgence is a striking example of how minor parties like United Future are feeling the squeeze.

Yet, NZ First has amply demonstrated it is possible to break that hold. Its current slump after touching 10 to 12 per cent in the polls is arguably self-inflicted. The support Winston Peters siphoned off Labour has bolted back home for fear he might put National into power - a fear he has so far refused to address.

In contrast, the Greens have guaranteed that a vote for them is a vote for a Labour-led Government. They are telling potential supporters who feel they must vote Labour that Labour needs a "sensible" coalition partner. Otherwise, Labour will be forced into the arms of Peters.

However, left-leaning voters may judge it wiser to strengthen Labour's hand in post-election negotiations in case that party ends up having no option but to deal with Mr Peters. The same logic applies even more to right-leaning voters as National will have to secure his backing to govern.

The squeeze currently going on the Greens, United Future, Act and, to a lesser extent, NZ First and the Maori Party may be eased by the electorate's taste for split-voting - about 40 per cent cast their two votes for different parties in 2002.

But this election is unusual. Normally, one of the major parties is in temporary decline. This time, both Labour and National are in pretty good shape.

You can quibble about detail, but they are both strong in terms of leadership, party branding, new policy ideas, demarcation on core issues, organisation, funding and determination to win.

They are squashing smaller rivals by muscling in on their issues while outbidding them when it comes to electoral inducements.

Critically, the increasingly ruthless and bitter contest between Labour and National is forcing voters to think about what they stand to gain or lose. It is forcing them to take sides - rather than taking out third party insurance.

While NZ First remains the exception, the minor parties are struggling to come up with something really fresh to say, only to find themselves drowned out when they say it.

The question now is not whether the minor party vote will recover, but who will panic first.