Assembly walesWith the General Election predicted to be rather boring in Wales, many people are already thinking about the 2016 Assembly elections.

The Welsh Assembly elections are more exciting, and are better for smaller parties. The regional seats – decided by a form of proportional representation – attract more parties, and a livelier debate.

Last week I predicted that the Greens could not win an Assembly Seat on their own. I now think I was wrong. I’ve attacked the problem, with a bigger spreadsheet, and some better data about voting intention in Wales.

I’m not trying to predict the entire outcome of the Assembly election. Rather, I’m trying to find a scenario in which the Greens could win an Assembly Seat. And then think about whether this scenario is at all realistic.

So here it is: a  scenario in which the Green party win two seats in the Senedd. Decide for yourselves whether you think it stacks up.

First it requires an upward swing for the Greens of between 40 and 60 percent, compare to the results for the last election in 2011. So in the Mid and West Wales region the Greens would need to jump from attracting about 8,500 votes to getting around 12,500. It would mean taking about 6% of the vote. This seems possible given that the Greens have been polling at about 5% across the whole of Wales, and this is one of their more popular areas in Wales. So the question for mid-Wales Green Party activists is: are there another 4-5000 Green voters out there and can they be convinced to vote green by May next year?

South Wales Central is in a similar position. The Green vote would have to jump from what it was in 2011 (10,774) to just under 17,000. A leap of about 55%. This means taking just over 8% of vote. This is at the upper end of what any poll predicts for the Greens across the UK. Are the another 6,000 or so Green votes in and around Cardiff? Let me know in comments what you think.

The other regions (North, South East and South West) are no where near as likely. Getting a seat in any of the would require the Green vote to jump by at least 140%. Or more like 180% in North Wales. I also don’t think there is much chance of the Greens taking a Constituency Assembly seat, as these are elected by Fast Past the Post. So the Mid and West Wales and South Wales Central regional seats are the most hopeful for the Greens.

This scenario also requires the virtual extinction of the Lib Dems. Their share of the vote in Wales would need to fall by about 45%. Labour and the Tories would have to do badly as well. Dropping by 23% and 28% respectively.

Is this possible? Maybe. Cardiff University compiles polling data on voting intention in Wales. They don’t break out the Greens in the data. Their analysis of voting intention in regional Assembly elections shows a 67% increase for “other” parties. (“other” does not include UKIP or Plaid). They also predict the 23% and 28% falls for Labour and the Tories I’ve used in the scenario. And the 45% crash for the Lib Dems. Remember also, that because the regional seats use proportional representation, people have always been more likely to vote for smaller parties. So I think my scenario isn’t completely outlandish.

Of course I couldn’t ignore UKIP in my calculations. The Cardiff University data shows them rising from 10% to 17% in the polls. A jump of 70%. If this is correct it could give UKIP 4 Assembly Members. I was shocked by this at first. But look at it like this: most polls have UKIP at around 16% of the vote. In an electoral system that is designed to better reflect vote share, you’d expect them to win 3 or 4 seats out of the 20 available.

So would this shake up the Senedd? A bit. Labour currently have a majority of 1. In my calculations they lose two seats, wiping out their over all control. But this isn’t that dramatic. If this happens they would probably form a coalition with Plaid, exactly as they did after falling short of a majority after the 2007 elections.

Could the Greens have a role, too?

Alex Randall lives in Machynlleth and has worked on a number of climate change campaigns and projects. He is writing here in a personal capacity.