Greg Hurst, Times political correspondent, says despite the frustrations of some voters the British National Party does not represent a credible political force - yet.

Why are white, working-class voters feeling frustrated with the main political parties?

The sort of frustration among some voters which the BNP is exploiting is concentrated in certain communities.There is no evidence that it is widespread among white working class voters generally.

Research commissioned by the Joseph Rowntree Reform Trust found that in Barking and Dagenham in East London people questioned in focus groups last year felt that the main political parties were not being truthful about the scale of immigration. They felt that Labour had failed them, but older voters aged over 45 blamed previous Conservative administrations too.

Is it just Labour heartlands which are affected, or are other parties involved?

The nature of these communities, which tend to be in poor inner city areas, mean they are much more likely to have Labour councils and MPs. Other than East London, the other areas of recent BNP activity include Bradford, Burnley, Kirklees and Oldham.

What are the grassroots issues that potential BNP voters feel are not being addressed?

Immigration is the central issue, although much BNP literature makes claims that asylum seekers and other immigrants have preferential access to public services. Housing and benefits, healthcare, local school places and similar issues can therefore be linked to such argument. Unemployment is another issue on which such fears can feed.

How has the BNP successfully appealed to former Labour voters?

Jon Cruddas, Labour MP for Dagenham, argues that the trend in recent general elections for Labour to concentrate its resources, campaigning activity and policy messages on floating middle class voters in marginal seats effectively ignores safe working class constituencies such as his own. He also says that there has been a step change in the professionalism of BNP campaigning, with higher quality materials and systematic canvassing.

It is important to stress, however, that the BNP has largely been unsuccessful in attacting supporters from Labour, and indeed from other parties, in large enough numbers to make itself a credible force. It has polled relatively strongly in some local authority wards and parliamentary seats, but not strongly enough to establish a big political presence.

Does the fear of being accused of racism make it harder for political parties to have a sensible debate about immigration, and local access to housing, education and healthcare?

Labour politicians have become more frank in discussing voters' concerns about immigration. David Blunkett was the most notable example as Home Secretary. But immigration remains a sensitive area of policy: politicians who discuss some of the practical policy questions that arise may be called racist, but those who hold back from doing so are accused of political correctness and risk ceding political ground to extremists like the BNP.

Michael Howard, the former Conservative leader, tried to tap into this feeling in the last general election campaign with Conservative posters saying: 'It's not racist to impose limits of immigration'.

How seriously is Labour taking this? Is the BNP a growing political force, irrespective of its small electoral chances?

The BNP is a tiny movement and not really a political force at all. There have been recurring fears among mainstream politicians that the BNP would make a political breakthrough of sorts, particularly with the advent of new proportional voting systems for the London assembly and the European Parliament elections. But these fears have to date not materialised.

What is more, a degree of scepticism is called for as Labour has track record of talking up the threat of the BNP before elections to try and get its core vote out.

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