For psephologists and related species of political tragic, by-elections can’t happen often enough. But for normal people, forced mid-term visits to the polling booth rank somewhere around brain surgery on lists of favourite things. No political operative should ever need reminding of this, but it appears the South Australian Liberal Party did — and now has been, in terms it won’t forget in a hurry.

Saturday’s preference count for the Frome by-election, held a week earlier upon the retirement of former Premier Rob Kerin, gave the Liberal Party the rudest of shocks three days after it had issued a press release claiming victory. Both Liberal and Labor scrutineers were convinced that Liberal candidate Terry Boylan had survived an early scare, thanks to Nationals voters who ignored the party’s recommendation to direct second preferences to independent candidate Geoff Brock. It was believed this would prevent Brock from getting ahead of Labor’s John Rohde, resulting in his exclusion at the second last count. That being so, the State Electoral Office’s indicative two-party count pointed to an unconvincing final Liberal margin over Labor of 1.7 per cent.

However, it seems scrutineers obsessing over the Nationals had neglected to consider the actions of Greens voters, who in the absence of guidance from the party’s how-to-vote card were thought to have followed their normal practice of putting Labor second. In fact, 42 per cent of Greens preferences flowed to Brock against 37 per cent to Labor — enough for Brock to emerge a bare 30 votes ahead of Rohde, before storming home on Labor preferences to defeat Boylan 9987 votes to 9322.

Before the evening was through, a Liberal Party that could previously be heard expressing nothing but warm goodwill about their good mate Kero suddenly found voice to complain about the “obscure” reasons given for his retirement, which had “fuelled resentment” among voters. However, this was clearly wisdom after the event.

Last June, The Advertiser’s Greg Kelton reported that “senior Liberals” were “hatching a plan which would force the Rann Government to face a ‘super Saturday’ of by-elections on the growing political row over changes to country health services”. This would involve the simultaneous retirement of Kerin (who was quoted saying the idea had been “mentioned a few times”) along with fellow Liberal veterans Graham Gunn and Liz Penfold, initiating by-elections in the country and outback seats of Frome, Stuart and Flinders. As bad as Frome has been for the Liberals, it appears that only the reluctance of Gunn and Penfold to bring forward their retirements has spared them a self-inflicted triple-barrelled disaster.

For all that, Labor shouldn’t get too cocky (and reports from The Advertiser that “gleeful Labor MPs have run off copies of Mr Hamilton-Smith’s ‘Liberal victory’ press release to hold up when State Parliament resumes next month to goad the Liberals” do not bode well in this regard). The two-party swing Labor would have picked up if Brock had run third had less to do with voters’ conscious preferences than with their adherence to how-to-vote cards, which in Brock’s case had Labor third and Liberal fourth. The 16.4 per cent of voters who deserted Labor might very easily find less benign ways to register their evident displeasure with the government when the next election is held in March 2010.

Cocky Labor MPs would do well to acquaint themselves with a forgotten episode of Western Australia’s recent political history known as the Peel by-election, which in February 2007 gave Labor a morale-boosting 1.0 per cent two-party swing from a strong performance on the primary vote — for all the good that did Alan Carpenter 18 months later.