Yesterday’s announcement of a snap election for September 6 was the second bombshell to hit WA politics this week, following Troy Buswell’s surprise resignation as Liberal leader on Monday. Uncharitable observers are making comparison to the events of 3 February 1983, when Malcolm Fraser sprang an opportunistic double dissolution on federal Labor in the failed expectation of locking the party in behind Bill Hayden. The distinction of course is that Alan Carpenter was aware the opportunity to face the disastrous Troy Buswell had already been lost three days earlier.

As always when an early election is announced, few are buying the official explanation that a poll is needed to “end the cynicism” and “clear the air”, particularly in light of Labor policy supporting fixed four-year terms. Opportunism being the name of the game, Carpenter would plainly have done better to have gone last week, with a recent poll suggesting Buswell was weighing the Liberal vote down by as much as 6 per cent.

Even so, there remains an overwhelming perception that Labor is in the box seat. Centrebet is offering a mere $1.18 for a Labor victory, against $4.25 for the Liberals.

The precedents for pre-election leadership changes have certainly not been promising, at least since Bob Hawke’s time: Robert Doyle in Victoria, Kerry Chikarovski in New South Wales and Bob Cheek in Tasmania all led state Liberal parties into the electoral mincer less than a year after taking the reins. The WA Liberals are further encumbered by the fact that Colin Barnett is their fourth leader this term, and they must also overcome new electoral arrangements that will require a notional gain of nine seats in a chamber of 59 to form even a minority government.

For all that, the Liberals have more going for them than interstate observers might assume. WA has hardly been a happy hunting ground for Labor in recent years: Geoff Gallop’s unspectacular re-election in 2005 was the only time the party’s primary vote has topped 40 per cent since 1989, a period covering seven federal and four state elections. Published polling during the Buswell period was not as bad for the Liberals as might have been expected, mostly putting Labor’s two-party lead at around 53-47. Buswell’s departure has also lanced a number of boils, reconciling vocal dissidents including former front-benchers Rob Johnson and Graham Jacobs.

Underdogs they might remain, but discerning punters should find those odds from Centrebet more than a little tempting.