Oz Politics Blog

For some time I have struggled to keep this site non-partisan. A particular area of difficulty in this objective has been the comments.

It has become clear to me that it was taking too much of my time to moderate the comments in an effort to maintain the non-partisan flavour of the blog.

It is with some sadness, therefore, I have decided to close down the comments feature on this site.

Update: For those of you who need the fix, I have put some links to discussion forums in the right hand side bar.

Yesterday, apparently, the Prime Minister told his troops that Labor had the “very formidable arithmetic challenge” of getting 17 seats.

I had been under the assumption that the number of seats Labor needed to win government was 16, and not 17. And so I had my own formidable arithmetic challenge: 16 or 17?

The 2004 election saw a House of 150 seats with 87 Coalition members, 60 Labor members, and three independents. Immediately following the 2004 election, to win government outright — ie. to have 76 seats in a house of 150 — Labor needed to win 16 additional seats. The mathematics is simple: 60 + 16 = 76.

There has been one by-election since 2004, in the seat of Werriwa. That by-election saw Chris Hayes (Labor) replace Mark Latham (Labor). It did not affect the number of seats Labor needs to win.

The have also been redistributions in New South Wales, Queensland and the Australian Capital Territory since the 2004 election. The redistributions saw no change to the number of seats in the House (150). One Coalition seat in New South Wales (Gwydir) was abolished and a notionally Coalition seat (Flynn) was created in Queensland. This does not affect the number of seats Labor needs to win.

According to the Mackerras Pendulum, the redistributions also saw two seats notionally change sides. Parramatta, currently held by Labor, becomes a nationally Liberal seat. And, Macquarie, currently held by the Liberals, becomes a notionally Labor seat. Because these notional moves cancel each other out, they do not affect the number of seats Labor needs to win.

In the seat of Calare, independent member Peter Andren has announced he will not stand for election in Calare in 2007. Instead he will contest the senate election. This changes Calare from an independent seat to a notionally Coalition seat. As a consequence, it does not change the number of seats Labor currently holds, nor the number of seats Labor needs to win government. However, it increases by one the number of seats the Coalition can lose before it loses government in its own right from 12 to 13.

As a result of the above, the Coalition notionally holds 88 seats. Labor notionally holds 60 seats. and the independents hold 2. The seats held by each party are set out in the following table. The notional seats are in italics.

Back to our “very formidable arithmetic challenge”. As far as I can tell, Labor still needs 16 more seats to win government in its own right (not the 17 reported).

Also, if the Coalition loses between 13 and 15 14 seats, and the number of independents remains unchanged at 2, the independents will decide which party forms government.

Update 8.45am 13/6: having thought about this some more, Labor would form minority government with an additional 15 seats. With an addition 15 seats Labor would have 75 seats, the Coalition 73, and the independents 2.

Even with the support of the independents, there is no way the Coalition could guarantee supply after providing one of its number as Speaker. After providing for the Speaker, such a Coalition minority government would proceed to lose every vote in the House 74-75. Section 40 of the Australian Constitution provides:

40. Questions arising in the House of Representatives shall be determined by a majority of votes other than that of the Speaker. The Speaker shall not vote unless the numbers are equal, and then he shall have a casting vote.

If the Coalition cannot guarantee supply, even with the support of the independents, it cannot form government. If the independents did not support Labor, the Governor General would need to call another election, as neither side can guarantee supply without the support of the independents. Only Labor can guarantee supply with the support of the independents.

So, Labor really only needs 15 additional seats to win government.

With the hypothetical uniform swing, using the election calculator, if Labor won 51.3 per cent of the TPP vote share it would win 75 seats. The last seat to fall under that swing would be Bennelong.

Today’s Courier Mail, Herald Sun and Daily Telegraph reported a Queensland-wide Galaxy poll of 800 voters last Wednesday and Thursday evening. The detailed poll results are here.

The predicted state-wide two-party preferred vote shares, were an election held last week, were 52 per cent for Labor and 48 per cent for the Coalition. That represents a 3 point movement from the February state-wide poll result of 55 to 45 per cent in Labor’s favour. But it is almost nine percentage points off the mark set at the previous election: 57.1 to 42.9 in the Coalition’s favour.

Update: Darryl Rosin identified an error in the 2004 results from the CM. I have corrected the 2004 election results above to reflect those on the AEC web site. Previously, I had used the figures from the Courier Mail

I have not produced an aggregated poll report since March. This latest look at the monthly aggregations is revealing.

It appears that Labor reached its peak in March, with 50.1 per cent of the primary vote and 60.0 per cent of the two party preferred vote. The Coalition’s primary vote reached its nadir in March: 34.9 per cent.

Since March, the Coalition has regained some ground in its primary vote. In May it was 37.2 per cent. But this has been largely at the expense of the Greens and the other minor parties.

What should be worrying for the Coalition is the resilience of Labor’s primary vote. From its March peak of 50.1 per cent it has fallen to 49.7 per cent. That is a negligible fall of 0.2 per cent per month.

The trend in the two-party preferred vote share reflects both the modest gains the Coalition has made in its primary vote and the resilience of Labor’s primary vote. From a nadir of 40.0 per cent in March, the Coalition’s two-party preferred vote share has climbed to 41.8 per cent. If it continued to climb at this rate — ie. 0.9 percentage points per month — it would reach 47.2 per cent in time for a hypothetical mid-November election. According to the election calculator, if the Coalition secured 47.2 per cent of the TPP vote, Labor would win the 2007 election with around 83 seats.

However, the Coalition’s TPP vote share can only continue to climb at 0.9 per cent per month if the Coalition becomes more effective at eating into Labor’s primary vote share. Otherwise the Coalition’s TPP vote share will plateau and Labor will win the election in a landslide.

In summary, Kevin Rudd increased Labor’s primary vote by 10 percentage points and so far he has managed to keep them. He moved the TPP vote eight points, but that has since moved back by just under two points. And, he moved the Coalition primary vote by six points, which has since returned by a little over two points.

The usual opinion poll graphs are here. You may need to hit the refresh or reload button on your browser to see the latest graphs.

The latest rise continues … last Sunday the average probability of a Coalition win was 43.1 per cent … last Wednesday it was 45.4 per cent … this morning it is 46.7 per cent. We have seen a number of these short-term mini-rises since Rudd’s ascension, For me the more interesting question is the medium-term trend.

The other graphs are here. You may need to hit the refresh or reload button on your browser to see the latest graphs.