There’s perhaps one finding we can take from the recent opinion polls — the Greens appear to be doing substantially better on this occasion than in the lead up to any past federal election. This morning’s Newspoll put the Green vote nationally at 14% and since the beginning of May it has hovered round the 13% mark.

Yet while the pollsters keep telling us that the Greens are on course to do substantially better at this election than in the past the pundits keep warning us that the eventual Green vote will be less than what is being predicted. Why that is the accepted wisdom of the media experts I’m not sure.

Looking at what has happened at recent elections seems to suggest, if anything, that the actual Green vote will be higher than the predicted one rather than the reverse.

15-08-2010 PREDICTEDGREENVOTEVSACTUALGREENVOTE

The opinion poll figure in the above table is the prediction in the second last Newspoll published before election day. In all four cases the actual Green vote was higher than the prediction.

The apparent myth that the Green vote falls away probably has its origins in what has happened in recent Tasmanian state elections where a slight fall did occur but those were quite different circumstances with the major parties both warning of the dangers to democracy of a hung Parliament in Hobart where the Greens had the balance of power. There is no such scaremongering in this federal campaign.

Hence my belief that on Saturday we will see the Greens gaining a 12 to 15% share of the national vote as is being predicted and if that happens there could be a few surprises in store for some Labor Party candidates in supposedly safe seats.

In a comprehensive and thoughtful paper for the Parliamentary Library in Canberra called The Rise of the Australian Greens, researcher Scott Bennett describes how the Green vote varies substantially depending on the type of electorate and the state. At the 2007 House of Representatives election when the Greens nationwide polled 7.8% of the votes, the figure for inner metropolitan seats was 10.8%, 7.6% in provincial seats, 6.5% in outer metropolitan seats and only 6.4% in rural seats.

15-08-2010 greensregionalfigures

Should this distribution pattern of the Green vote be repeated this Saturday then, taking a mid-point of what the recent polls have predicted nationally, a 13% Green vote would turn into an 18% share of the vote in inner metropolitan seats.

15-08-2010 greenvoteinmetropolitanelectorates

An 18% share of the vote across all inner metropolitan seats is getting close to the level where several seats would see the Greens vote higher than that of the Liberals which is one precondition for a potential Green House of Representatives victory. A second requirement, naturally, is that Labor does not get above the 50% mark so that Liberal preferences have to be distributed.

15-08-2010highestgreenvotes2007

If we do happen to see a seven or eight percentage point increase in the Green vote, with almost all of it coming from Labor, then it is not only the inner city seat of Melbourne where Labor will be in trouble. Sydney, Denison and perhaps Grayndler would enter the endangered list.