Some 16 days on from the election, progress in the Senate count quickened a little yesterday as the count in the House winds down. Counting is still slow, though, with between 1% and 2% of votes added in most states.

But as far as the news media was concerned, it was one of two red-letter days in the progress of the Senate count so far. This was due not to any dramatic reversals or uncovered anomalies, but to what remains for most the only way to get a handle on the process — the output of Antony Green’s Senate election calculators on the ABC website.

On this measure, the prognosis for the Western Australian count was dramatically transformed, with both Greens Senator Scott Ludlam and the much-feted Wayne Dropulich of the Australian Sports Party suddenly appearing to be headed for defeat at the hands of Labor Senator Louise Pratt and Zhenya Wang of the Palmer United Party (who, party label aside, is hardly better known than Dropulich).

As has so often been the case at this election, this has very little to do with the will of the electorate and a lot to do with the order in which seemingly insignificant candidates are excluded from the count. The key change has been at what the ABC projection identifies as “Count 21”, which previously had the Shooters and Fishers last out of 10 remaining candidates, just behind the Australian Christians.

In one of the election’s more understandable preference allocations, the Australian Sports Party received a high placing from Shooters and Fishers, whose exclusion stood to keep Dropulich alive as the next few stragglers were excluded. But with the Australian Christians now projected to get the chop instead, Dropulich stands to be excluded at the very next count.

Of the micro-parties set to survive that far into the count, none has done quite as well as Australian Sports Party in harvesting the preferences of the others. That means Dropulich’s exclusion would result in the seat going to a party that did actually secure a serviceable share of the vote, namely the Palmer United Party.

The rub for Ludlam is that he was relying on Palmer preferences to get ahead of Pratt, who would then fall victim to a shockingly bad result for Labor in WA that would reduce the ALP to just one out of six Senate seats (as has been the case in South Australia, where Labor at least had the excuse of competing with the Nick Xenophon juggernaut).

The other development of late Senate counting to arouse excitement (as well as giving beleaguered election analysts a chance to enliven their copy with sexual innuendos) came last Tuesday when a switch in the projection for Tasmania gave the last seat to Robbie Swan of the Sex Party. That dislodged the third candidate on the Liberal ticket, Sally Chandler, who had herself overtaken the Palmer United Party’s Jacqui Lambie a week previously.

With only a trickle of votes left to come, we are unlikely to be seeing further changes in the ABC computer projections. However, the election result itself is a different matter, due to the unavoidable weakness of the Green model: its inability to take into account below-the-line votes.

Normally this isn’t a decisive factor, but this time the closeness of the counts at so many crucial points means tiny alterations can have a crucial bearing on the result — particularly in Tasmania, where the rate of below-the-line voting is over 10%.

Presently the AEC is engaged in the task of data entry on each below-the-line ballot paper, which in the case of Tasmania at least is approaching conclusion for a computerised preference distribution to be conducted tomorrow. Other states may have to wait until early next week.

The table below gives a sense of the range of possibilities that the government will face when the new senators take their seats in the middle of next year, assuming WA and Tasmania to be the only results still up in the air. However, it should be observed that the blogger TruthSeeker, who has been offering the best publicly available modelling of potential outcomes, has kept open the possibility of a few other late surprises …

Senate results

The least unlikely of these involves the Coalition failing to win a third seat in New South Wales, with Arthur Sinodinos most likely losing out to Shooters and Fishers (the election of the Liberal Democrats to one of the other five seats being a given). Other remote yet still conceivable possibilities are that the micro-party seat in WA will in fact go to the Liberal Democrats, or that No Carbon Tax Climate Sceptics win the seat more likely to go to Family First in South Australia, despite having polled only 0.11%.

To keep things manageable, the table leaves all that aside and considers two alternative outcomes in WA and three in Tasmania.