World: Analysis - Can advertising offer an edge when it comes to voting day?

Closely contested election campaigns attract greatest adspend.

Americans are going to be seeing a whole lot of it this year and it will probably be nastier than ever. Brits will have to wait for next year and there will be no shortage of potential topics. In Spain, it was largely overtaken by terrorism; in Russia, it was thin on the ground and probably wouldn't have made much difference anyway.

It is political campaigning and the amounts spent by candidates trying to convince the electorate that they are the ones to vote for can vary hugely from country to country: in the US, it's estimated that dollars 1.3 billion will be spent, while in Russia, the amount was negligible.

But how effective is it? Can it swing an election? Do people actually pay any attention to it at all?

Will Harris, the Conservative Central Office head of communications, says: 'My view of political advertising is that it can be incredibly effective, but it's very difficult. Get it right and you capture the mood of the nation. The reason it's difficult is because you're trying to hit a moving target. You might feel the same way about a brand of soft drink for a year, but public opinion never stands still.'

Andrew McGuinness, the chief executive of TBWA\London, the agency behind New Labour's advertising for the last election, unsurprisingly takes a similar line: 'It plays a very important role. It crystallises the arguments of the candidates in an election period. A great piece of advertising should communicate in a single image what candidates have been saying for months.' In the last election, the poster showing William Hague crossed with Margaret Thatcher united many abstract themes in a memorable and humorous image.

In many ways, such iconic imagery is what the UK does best in terms of electioneering. TV advertising in the UK is limited to party political broadcasts which are, in the minds of many, synonymous with switching over or turning off.