Labour has a southern problem. Unless Gordon Brown solves it, his party will not win a fourth term. The talk by the Labour deputy leadership candidates during the current hustings about “reconnecting” with core members and voters in the party’s heartlands in the Midlands and the North is not enough.

Fifteen years ago, after Labour’s fourth defeat, Giles, now Lord, Radice wrote a Fabian pamphlet, entitled Southern Discomfort, which was based on research among swing voters, mainly skilled working-class families in target seats in the South East. This underlined how Labour had failed over the previous decade to identify with their aspirations and insecurities.

The pamphlet had a big influence on the party’s rethinking in the early 1990s and on the development of new Labour strategy under Tony Blair. The lessons learnt were reflected in the party’s big electoral gains in the South in 1997.

However, as Lord Radice, now chairman of the Policy Network, the international centre-left research group, noted recently, Southern Discomfort may be reemerging in a new form. Half of Labour’s most vulnerable seats are in London and the South East and along the M4 and M1 corridors. From 2004 onwards, the party has been steadily losing ground in the South.

At the 2005 general election, Labour lost 13 MPs in the eastern, southeastern and southwestern regions, leaving 45, many with wafer-thin majorities. (This is apart from London, where Labour now has 44 MPs, having lost 11 two years ago.) So a further loss of support in these regions could rob Labour of its Commons majority.

The omens are not good. Labour suffered big losses in the South in the local elections on May 3 and now controls just two of 89 district and unitary authorities outside London. So, as Lord Radice says: “It is not so much Scottish Discomfort but Southern Discomfort which is the real threat to Labour.”

The same theme was taken up in a Fabian lecture on Wednesday by John Denham, one of the most thoughtful Labour backbenchers, who resigned over the Iraq war and deserves a recall to the Brown team. He was one of the vanguard of Labour MPs to gain a seat in the South in 1992, at Southampton Itchen. He challenges common stereotypes about a Tory-voting wealthy South which is inherently hostile to Labour.

The South is certainly better off than other regions, but it is also experiencing all the pressures of the globalising economy, mass migration and climate change. There are acute problems of housing shortage, particularly for young people, and a squeeze on public services. The combination of national scales for social benefits and higher living costs means that, in relative terms, to be poor in the South is to be poorer than in other parts of Britain.

Mr Denham argues that Labour’s declining vote, especially among women, shows that “too many southern voters are no longer sure we understand their lives or that we speak for them”. There are a whole range of policy implications. One priority is to address job inequalities, since the region includes many losers as well as gainers from globalisation and migration. The impact is not evenly distributed. Eastern European workers may be good for the economy, but not for unskilled young men.

Many of these social problems naturally occur elsewhere in the country and Labour also has plenty of vulnerable seats among the 64 it still holds in the East and West Midlands. But Labour cannot rely on David Cameron’s failure to make big inroads in the North and the stalling of the Tory momentum in the Midlands (as reported yesterday by Francis Elliott). Gordon Brown has to become a man of the South.

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