‘Which part of “send them back” don’t you understand, Mr Blair?’ These were the words the Conservative candidate, Bob Spink, chose to enthuse the people of Castle Point to vote for him at the election. It was a sentiment with which the voters in this Essex seat evidently agreed: Spink was re-elected with a majority of 8,201, more than eight times the majority he achieved in 2001 when he took the seat back from Labour.

Whether the Conservatives’ relentlessly anti-immigration campaign appealed as much to the country as a whole, however, is less certain. Although the party managed to increase its MPs by 31, it did so with only a 0.6 per cent increase in its share of the national vote. As the Tories look to their prospects for winning power in 2009 or 2010, one question will undoubtedly be playing on Conservative minds: did a campaign that sought to exploit public fears over immigration so openly do them any good?

In some areas, the answer seems to be yes. Luke Akehurst, the Labour candidate in Castle Point, believes the Conservative campaign tapped a deep seam of resentment with voters in this predominately white, lower middle-class constituency, where turnout in the election rose by 7.5 per cent. According to Akehurst, much of the resentment stemmed from the perceived economic threat posed by recent immigrants to the capital from Eastern Europe.

Croydon Central, home of the government’s asylum-claim processing centre, Lunar House, is another London seat where the Conservatives’ anti-immigration message may have worked to its advantage. During the campaign, the Tory candidate, Andrew Pelling, canvassed the predominately white housing estate of New Addington in the constituency with a leaflet titled ‘Unlimited immigration?’ and an arrow pointing directly to Croydon. He went on to win a majority of just 75 over the Labour incumbent, Geraint Davies.

Davies’ agent, Steve Buckingham, however, is anxious to highlight other factors in the Conservatives’ success. Labour, he says, was less popular in Croydon for a number of reasons, including the Iraq war and perceptions about antisocial behaviour, trust and council tax. On such a small margin, he believes, any one of these issues could have contributed to the party’s defeat. The Conservative candidate was also keen to emphasise his links with the Muslim community in the area during the campaign.

Similarly, in some seats the Conservatives gained, such as Putney in London, local candidates appeared to place some distance between themselves and the national party’s stridently anti-immigration message. And, in other areas of immigration-related tension, the Tories’ tactics do not seem to have had an impact. In Keighley, a seat that has seen conflict between its white and ethnic minority communities and where the BNP’s Nick Griffin stood as a candidate, Labour’s Ann Cryer managed to increase her majority over her Conservative opponent. In Dover, the Tory candidate, Paul Watkins, saw his share of the vote decrease, despite the area’s tabloid notoriety as the asylum ‘gateway’ into Britain.

Why does the Conservative campaign seem to have had resonance in some areas but not in others? According to Shamit Saggar, a political scientist at Sussex University, most people see immigration as a matter of government competence rather than policy. Their main concern is not whether immigrants should be let in, but how well the system is managed once they arrive. Rightly or wrongly, immigration is widely believed to be out of control. However, the issue is only one indicator of how well the government is doing.

This analysis may explain the regional differences in the impact of the Conservative campaign. In the south-east, where there was a three per cent swing from Labour to the Conservatives, concerns over immigration, together with issues such as over-congestion and council tax, fed a general sense of dissatisfaction with the government. However, in the rest of the country, where Conservative support stagnated and even declined in some regions, immigration did not prove the decisive issue with voters that the Conservatives had hoped.

Ultimately, the Tories’ strategy probably cost them more votes than it gained. In particular, Howard’s negative message seems to have put off the large number of floating voters the Conservatives needed to regain power. Polling shows the immigration issue to be of far less interest to women than men. At the election, only 32 per cent of women who voted backed the Conservatives, while Labour gained 38 per cent of women’s votes, securing a comfortable victory for the party. What might have worked in Castle Point does not seem to have worked in the country as a whole.