Why is the Tasmanian Labor government about to act on gay marriage when, 15 years ago, it was just about the last in the civilised world to decriminalise s-x between consenting male adults?

Why is the Tasmanian Labor government seeking to lead the way nationally on caged hens and ending the use of sow stalls for pregnant pigs?

Why is the Tasmanian Labor government between a rock and a hard place on forestry?

The answer to all of these questions is to be found in a graph of opinion polling of Tasmania’s political parties over the past seven years. The graph shows Tasmanian Labor in the wilderness. But all is not lost.

Pollster EMRS data shows Labor support on a downward trend from a high of 49% support in 2006 to below 20% today. The Liberals’ trend line is climbing, gradually, from 23% in 2005 to 38% today. The Greens’ trend line follows a similar upward path, from 12% seven years ago to 17% today.

Tasmanian Labor has lost its progressive vote to the Greens while the Liberals are holding the ground of the centre-right. Tasmanians no longer know what Labor stands for. The Greens are stealing its heartland.

So we saw the move at the weekend by Labor to seek to re-establish its social progression by moving to allow gay marriage, another Green initiative. Commentators proffer the view that this is Labor seeking to distract the electorate from the ills of the economy, the continuing impasse over forestry, etc., fiddling while Rome burns, if you like. After all, they reason, this law reform is not going to go anywhere because it has to garner a majority of votes in the 15-seat upper house and that looks doubtful.

And, if it were to pass the Tasmanian Parliament, would it withstand a High Court challenge that presumably would be fought on the basis of a conflict of state and federal law and Constitutional Law 101 says that where there is such a conflict, federal law will prevail?

Meanwhile, Hobart talkback runs hot with calls of outrage from the Christian lobby.

Back to the graph. Examine the entrails. Common wisdom is that Labor will get a bath at the 2014 state election. Many go on to conclude that it means Labor will be driven from office.

It ain’t necessarily so. Without going into the intricacies of the Hare-Clark system that is used to elect the 25 members of the Tasmanian House of Assembly, let me explain what may happen.

We have five MPs in each of five electorates, elected by proportional representation, very similar to the Senate. In 2010 Hare Clark delivered what you would expect: 10 Labor, 10 Liberals and five Greens, 2:2:1 in each electorate. Labor and the Greens joined forces to form a 15-10 government.

To win majority government, a party has to win three seats in each of three electorates (and two each in the other two). That means they have to secure 49.8% of the vote in each of those three electorates. The Liberals, under leader Will Hodgman, are not getting anywhere near that level of support, particularly in southern Tasmania. They are below 40%.

What are you left with? Despite Labor’s appalling stocks, the Greens and Labor, in their combined vote, are closer to 50% than the Liberals. Between them they can see 13 seats. The Greens may be growing in support and Labor declining, but the end result is the same.

This whole social reform exercise in Tasmania is about damage minimisation, consolidating Labor’s progressive vote to shore up 13 seats with the Greens and to keep the Liberals from governing.

It is Liberals who have the bigger problem.