“IT’S NOT racist to impose limits on immigration,” say the posters. But is it politically wise? Political strategists who criticise the Tory campaign argue that Michael Howard’s emphasis on immigration is simply a repeat of William Hague’s campaign in 2001. And we all know what happened at the end of that.

Raising the immigration issue has two potential electoral drawbacks.

First, pollsters point out that the Tories are already well ahead on the issue and yet are not winning overall. This may mean that they simply need to make it a bigger issue, but it is more likely to mean that many of those who agree with Mr Howard on immigration are either already Tory or do not regard it as a clinching issue. Time spent talking about immigration is time not spent closing the poll gap on the economy. The second possible drawback is that campaigning on the issue may actually alienate some of the AB social class voters the Conservatives desperately need in order to win marginal seats. Some professional women, in particular, do not like it.

For vast numbers of voters, however, immigration is a big issue indeed and many more of them agree with the Tories than with Labour. There have not been many issues like that since Tony Blair invented new Labour. So it is understandable why the Tory campaign thinks that talking of potential drawbacks is just quibbling.

• Daniel Finkelstein was director of research and policy of the Conservative Party in the 1997 and 2001 elections.

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