About those "others"

A lot of interpretation of the polls now is rather skewed by the 20% or so that is still going to others. For example, the Conservative share is still seen in the light of whether they need to be over 40%, and we gasp at Labour being down in the low 20s. Both these are a factor of the "others" being up at 20% or so, suddenly there is less support for the main three parties to share.

This makes rather a mess of our heuristics. Normally saying the Conservatives need to be 40+ is a pretty decent rule of thumb, because its very rare for Labour to drop below the high 20s, so 40+ is what the Tories need to have a lead large enough to win a majority. With a big chunk of support going to "others" and Labour pushed down into the low or mid 20s, suddenly it's perfectly possible on paper for the Conservatives to get a stonking victory below 40%. In terms of national swing it's the lead over Labour that counts: Conservatives 42%, Labour 38% has the Conservatives above 40%, but might well leave Labour the largest party. Conservatives 38%, Labour 22% has the Conservatives under 40%, but would translate into a towering landslide victory.

There is also a tendency to talk about what happens when the other vote recedes. The largest chunk of it tends to belong to UKIP, and the broad assumption is that those voters are more likely to move to the Conservatives rather than Labour (though it's not a given – the assumption that UKIP voters would all otherwise vote Conservative is false). It does depend, anyway, on the assumption that the other vote will go down. It hasn't so far.

On balance I expect it will, but not yet. The reason is on the graph below.

This shows the level of support for "others" in the polls in the last Parliament. The effect of the European election is obvious - a great big spike in support in mid 2004. Notably, it did not immediately disappear once the European elections had passed, it decayed very slowly, but steadily, over almost a year.

Now, the present increase in support for others is, to some extent, almost certainly due to the same reason - the publicity and respectability given to smaller parties by the European elections. With that it mind, I wouldn't expect it to vanish immediately either, as in 2004, I'd expect it to decline only slowly over several months.

The complicating factor here, of course, is the expenses scandal. Part of that increased support is probably nothing to do with the European election, and is instead down to the expenses scandal. I'd expect that to decay as well to some extent, since the exposes have finished and the news agenda inevitably rumbles onwards, looking for new stories, new issues, new focus. To what extent these people come back, however, is much more of an unknown quantity.