Blunt instruments that can hammer home the message

The 1997 election campaign is being presented as a sophisticated exercise in state-of-the-art communications. But despite all the hi-tech innovations, the biggest outlay of Conservative and Labour funds is actually going on the oldest, most traditional advertising medium of all: posters.

From the birth of modern political advertising with the pathbreaking 1959 Tory campaign ("Life's better with the Conservatives - Don't let Labour ruin it"), its costs have greatly exceeded those of other forms of electioneering. But in the Sixties, Seventies and Eighties the bulk of this money was devoted to press ads, which often featured substantial closely argued text. In the Nineties we have witnessed the growing "posterisation" of political advertising, as parties increasingly focus their efforts on simplistic slogans.

From the local elections last May to the end of March, the Conservatives spent an estimated pounds 5.2m on posters, 83 per cent of their total advertising spending of pounds 6.3m. Labour spent an estimated pounds 2.8m on posters, 78 per cent of a total ad spend of pounds 3.6m. This represents an intensification of the emphasis on posters started at the 1992 election, when 69 per cent of Tory ad spend and 53 per cent of Labour's went on billboards.

And the political poster war is escalating. Both parties have thousands of hoardings booked until polling day. According to industry sources, the Tories are splashing out a further pounds 3m-plus on posters this month, and Labour pounds l.5m. While the Conservatives used a few press ads last week to launch quickfire tactical attacks on Labour over Europe, this does not affect the trend.

The Referendum Party, which has been the biggest overall spender so far, is alone in ignoring this trend: pounds 5.1m (78 per cent) of an estimated pounds 6.5m spent on advertising since last May went to the press. The cash- starved Liberal Democrats have been spending next to nothing on any form of advertising.

The two main parties' concentration on billboards partly reflects the increasing efficiency of the poster industry. In the Eighties, advertisers who booked poster campaigns could never really feel sure that their posters were going up in the right places at the right times. "The industry was chaotic, but it's been revolutionised," says David Pugh, commercial director of the poster company Mills & Allen, which along with its rival, Maiden Outdoor, owns most of the large roadside hoardings that parties use. "Advertisers sitting in London buying a campaign can now be confident that posters will go up on a wet Wednesday morning in Sheffield when they're supposed to."

Posters are the visual equivalent of soundbite politics - a striking image accompanied by a stark slogan. They reflect the need for parties to communicate with many voters superficially; and simultaneously they reinforce it.

Labour, for example, has reduced its five pledges to the most simplistic of summaries, such as "Young offenders will be prosecuted". The latest Tory posters simply says "Boom" with a blue background, and "Gloom" backed by red.

"If your message is image-driven, then posters are great," says Mark Hartstone, head of planning at the ad agency FCB. "They have high visual impact with emotionally motivating headlines. If you were selling something complex with detailed explanation, then you should be better off advertising in the press. But most people won't read in-depth political coverage. That's sad and it worries me."

It's one thing the parties agree on. "It's not desirable but it has to happen," says a senior figure working on Labour's account at ad agency BMP DDB. "People need a headline under which to understand a party's message. It's our duty to reduce things to a central core."

The admen for both sides agree too. Over at M&C Saatchi they say: "Posters are good for the simple image which sticks in the mind. We believe in blunt instruments. We are the hammer of the campaign."

Posters also communicate with the parts of the electorate that other media can't reach - the election avoiders, who don't want to watch TV news about the campaign or read about it in the papers.

Viewers have already been abandoning the extended Nine O'Clock News with its detailed election coverage, but these people will only be able to evade party posters at the cost of staying indoors until polling day. And they tend to be crucial floating voters. "If you're out and about, you can't miss posters. You can't switch off or turn the page. And by the time you've looked at the poster, you've got the message," says David Pugh of Mills & Allen.

Martin Rosenbaum is the author of "From Soapbox to Soundbite: Party Political Campaigning in Britain since 1945" (Macmillan).