The potential for UKIP to attract Conservative votes gains much attention. So does the implication that it clear Ed Miliband’s path to Downing Street – even if Labour only win 35 per cent of the votes cast at the General Election on May 7th 2015. “Vote Purple Get Red” – or “Vote Purple Get Yellow” – will be the warning.

Much less attention has been given to the Green Party. Yet they represent an equivalent source of anxiety for Labour and the Lib Dems. Perhaps Labour will transpose the Cameroonian slogan: “Vote Blue, Go Green”.

At the last General Election, the Green Party stood in fewer than half the constituencies and achieved one per cent of the vote. Under the circumstances getting an MP elected was impressive.

Surely they are likely to do better on 2015? The YouGov poll published yesterday had them on five per cent. The Populus Poll yesterday had them on four per cent. Often they poll a bit higher – six or seven per cent.

What may not be understood by all their supporters is that the Green Party is on the extreme left. Those refugees from Michael Foot’s Labour Party circa 1983 would (and sometimes do) find themselves at home there. They can sing the old tunes. Higher tax, renationalisation, smash capitalism, no to NATO – all the predictable themes.

The image the Green Party enjoy is of an eccentric but well meaning outfit – that means that they tend to get a soft ride in the media. It has meant that some Liberal Democrats, wishing to indulge in an anti establishment gesture, switched to the Green Party rather than Labour. The reality remains that the Greens are not so cuddly but often prove to be an unpleasant, intolerant party.

Ian Warren provided an interesting analysis recently on which seats the Green Party might target. He notes that 10 per cent of those who voted Lib Dem at the last election intend to switch to the Greens next year. Mr Warren has been crunching the polling data to consider the demographics of Green voters – they tend to do better among younger voters for instance – and the middle class. He list those constituencies offer fertile territory for them – on the basis of those who with highest proportion of the favourable demographic groups:

Here are the top ten:

Cardiff Central (41.1% of households) – 13% Lib Dem majority

Sheffield Central (39.7% of households) – Lab maj. of 0.4% over Lib Dems

Bristol West (37.6% of households) – 21% Lib Dem maj over Lab

Brighton Pavilion (36.7% of households) – Green-held

Manchester Withington (33.9% of households) – Lib Dem maj of 4.1% over Lab

Wimbledon (33.6% of households) – 24% Con maj over Lib Dems

Newcastle-upon-Tyne East (30.6% of households) – 12% Lab maj over Lib Dems

Tooting (30.6% of households) – 5% Lab maj over Con

York Central (29.5% of households) – 14% Lab maj over LD/Con

Hove (28.7% of households) – 3.7% Con maj over Lab

Mr Warren adds:

“In many of these seats the Green Party can reasonably expect to increase its vote share, with the possible exception of Brighton Pavilion where one can plausibly make the case that every percentage point of Green support was maximised to the full in 2010. The assumption at this stage must be that the Lib Dems will lose many voters from 2010, and a good proportion of them have shown in the local and European elections that they are not averse to voting for the Greens. The challenge for the Greens is to retain those voters in 2015. If the polls are to be believed then 10% of 2010 Lib Dems have already decided to vote for the Greens in 2015. If these intentions do convert to votes it will hardly shake the political landscape, but it is at least worthy of some attention.”

The Green Party have just been holding their annual conference in Birmingham. In her speech their Party leader Natalie Bennett claimed that Party membership had risen by 28 per cent in the past year and that the Party would contest “at least” 75 per cent of constituencies in the General Election next year.

She went on to say:

“For the 2015 general election will be unlike any before. We’re now a parliamentary party, after Brighton Pavilion elected Caroline Lucas in 2010. I’m confident it will re-elect her in 2015, and that Norwich South can send Lesley Graham to join her, while Bristol West can add
to the West Country’s tally of Green parliamentarians with Darren Hall.

“We can become strong challengers and make breakthroughs in Liverpool Riverside, in Oxford East, just up the road in Solihull, in St Ives, in Sheffield, in York and in my own home territory of Camden, in London.”

Some of these seats are Labour/Lib Dem marginals – it is difficult to predict what impact an increased vote for the Green Party  might have. Perhaps the Greens will take a similar number of votes from Labour and the Lib Dems and thus see their significance neutralised.

But there could well be a handful of Labour-held seats where the Green Party represent a serious threat. That could prompt a diversion of money and manpower by Labour from campaigning in seats they need to gain. It puts them on the defensive. More generally the Greens offer an impediment to Labour in seeking to hoover up all the votes of disaffected Lib Dems.

Politics is becoming more fragmented on the Left as well as the Right. What if half a dozen Green MPs and that they would be needed by Mr Milband as coalition partners? Mr Miliband should be challenged to rule any deal with such an outfit – it would be as bad as making George Galloway a cabinet minister.