Hardly an analysis of Labor’s surprise close shave in the Northern Territory has failed to make note of the other campaign in progress in Western Australia. Certainly the two elections have much in common: both involve Labor governments that came to power unexpectedly in 2001, seeking third terms after a mid-term leadership change. However, the main cause of excitement has been that both Alan Carpenter and Paul Henderson rushed to the polls ahead of schedule, acting with all the cynicism that early elections invariably entail.

Henderson’s decision to go 11 months early was made on the pretext that an environment of “certainty” was needed to assist the Territory’s bid for the Inpex gas plant, which failed to ring true given the Opposition’s equal enthusiasm for the project. How much this had to do with the result is hard to say. The conventional wisdom has been that bad publicity attending early election announcements is usually washed away by the tide of the campaign, leaving more pragmatic concerns to guide voters’ judgements on polling day.

Certainly there are alternative explanations for the Northern Territory election, not least that it was a correction after an extraordinary result in 2005 that had no parallel in Western Australia. No party should ever feel pleased with a swing of over 8 per cent, but Northern Territory Labor still recorded its second best ever result in primary vote terms and equal second in terms of seats. There is also the fact that the party had effectively knifed the leader who delivered them the 2005 landslide, for reasons that would have seemed obscure to those without their noses to the political grindstone.

In one sense the early election in WA is a less extreme circumstance in that Carpenter has gone only five months ahead of time, after laying the groundwork with talk of a “dysfunctional” parliament that had most bracing for a poll in October. However, of more significance than the timing was the political context: Carpenter called the election on Thursday just one day after Colin Barnett returned to the Liberal leadership, clearly having fast-tracked the existing timetable to catch his opponent off balance.

The historical record provides some support for the idea that early elections comes with risks attached. John Howard’s near-defeat in October 1998 came five months ahead of time, as did Bob Hawke’s disappointing performance in December 1984 (the 1983 double dissolution meant a half-Senate election had to be held no later than mid-1985). Jeff Kennett went six months early with both his bids for re-election, with respectively unremarkable and disastrous results. Those with longer memories might recall Labor’s unexpected defeat in South Australia in 1979, when Des Corcoran surprised his own party by going a full year early. On the other hand, Peter Beattie performed strongly in 2006 when he like Carpenter opted for a September poll that wasn’t due until February.

If the effect varies according to circumstance, Carpenter’s early poll might still be said to have a lot going for it. While the Liberals have been busy retooling their advertising campaign around a new leader, Carpenter has been able to trumpet his government’s achievements to mass television audiences captured by the Olympics. There is also talk from political insiders of empty Liberal Party coffers, which might have been filled if Barnett had been given more time to restore the party’s electoral credibility.