On this the parties are incurious. They seem not much interested in the subject. Earlier this year when I raised it with a veteran Tory campaigner who is close to the Prime Minister, he waved away the question about immigrants: "They don't vote, they won't vote. They're not interested."

Some noises have emerged from Tory headquarters that suggest there will be, in the dreaded modern phrase, "outreach" to immigrants. But the thinking seems to be in its earliest stages. Someone close to Ed Miliband also agreed that it was an interesting area, and that he would think about it. He is still thinking.

Perhaps it is unsurprising that the parties are being slow here. This immigration has happened so rapidly and on such an enormous scale that understandably it is taking people time to catch up and to work out the implications. Equally, that is true in academia. At the Migration Observatory at the University of Oxford, there is already an impressive body of research and analysis assembled. But Dr Scott Blinder, who leads the team at the Observatory, acknowledges that some areas of study are only just getting under way. "It takes some time for people to recognise that this is an important subject and to work out how to study it. And the data takes time to accumulate."

Blinder is a political scientist interested in the impact of migration on voting behaviour. The complication is that not all immigrants can vote, and some may not even want to. Those who have arrived from Eastern Europe can vote in local and European elections, although they cannot participate in general elections. It can take up to six years to go through settlement and to get British citizenship. As Blinder says, if they can do everything else bar vote in general elections, many immigrants from within the EU might conclude that they are not missing out on much and decide it is not worth becoming British, but still choose to stay here for work.

Indeed, as yet very few Poles are opting for naturalisation. This is despite the establishment of huge new Polish communities in places such as Colchester, where the Catholic churches have had a new lease of life and services in Polish have been laid on. But in 2011 only 1,863 Poles in the entirety of the UK became British.

However, as Blinder observes, the Poles and other Eastern Europeans who arrived after 2004 are having children who will have full citizenship rights. In Boston, Lincolnshire, more than 10 per cent of the population and 62 per cent of those at school are from Eastern Europe. The first of those children will be eligible to vote in a general election early in the next decade. "These kids won't be migrants, but they will be the children of migrants," says Blinder. This raises fascinating questions about assimilation and how different their outlook will be. "There is good reason to think they might be distinctive electorally. Look at ethnic minorities," says Blinder. Ethnic minorities are more likely to vote Left.