'I always support the lower classes': Jimmy Cliff's response to his adoption by Cameron

Even those who had doubted their leader now seem convinced that he is the man to lead them back to power. The Tories are so excited that they have even posted a film of the party leader's moment of glory on their website, citing the song as part of the success of his closing speech.

But the reggae classic has roots that would drain the blue rinse from those who chanted along so chirpily; roots more associated with drugs and violence than the values that Conservatives hold so dear.

Jimmy Cliff's song was the main score of the soundtrack to his film The Harder They Come; a Jamaican exploration of marijuana, gun crime and gang violence. The psychedelic poster for the film gives a hint of what is to come: a gun-toting gangster straddles a car, dressed in bling jewellery, sunglasses and a leopardskin shirt, he points the barrels of his shot guns menacingly in the air.

And no one is more bemused by Cameron's song choice than Jimmy Cliff himself – or Dr Cliff, as he now likes to be known. "I've never voted in my life", he said by telephone from the Jamaican capital, Kingston, yesterday. "But I'm from the lower class of society and I tend to support them rather than the upper class. It's not that I don't have friends or family in the upper classes – I do – but I always prefer to support the lower classes."

The singer had just been told of his song's political use, and made it clear he was no Cameronian. "One of my band mates called me this morning to tell me the news. I can't stop them using the song, but I'm not a supporter of politics. I have heard of Cameron, but I'm not a supporter. I don't support any politician. I just believe in right or wrong."

Cliff makes an interesting choice for the Tories. Last night, a party spokesman said: "The song makes a good point, which echoed the theme of the conference: that if the public really want change they can have change."

But, when confronted with some of the Conservatives' policies – in particular their hardline stance on drugs - the singer said: "I'm not for hard drugs, but I don't think marijuana should be against the law."

Cliff has been outspoken in his songs, in particular using them to campaign for freedom and human rights. It is unlikely that the he will want his song to be a soundtrack for the establishment if it becomes the Tory election anthem.

Although Cliff has reservations about the use of the song on the political stage, it isn't first time it has been used in a bid for power; for it was also the choice of the Sandinista National Liberation Front in Nicaragua.

Certainly the imagery of the The Harder They Come is a far cry from the meek oak of the rebranded Conservatives. Directed by Perry Henzell, it has been credited with the emergence of reggae culture in America – a movement that was about much more than music.

Drugs feature heavily in the film, which follows the character Ivan O Martin, played by Jimmy Cliff himself, and based on the notorious Jamaican outlaw Ivanhoe Martin. The soon-to-be notorious Ivan heads to Kingston to find fame as a reggae star, before getting sucked into a world of drugs and crime. The film's scenes of violence and drugs still shock modern audiences. But graphic knife fights are just the beginning for this ground-breaking film, which showed that dealing in ganja was far more profitable than the record industry for an up-and coming artist. The film ends in a showdown of bullets, but does not really come down on the side of the police: hardly a conclusion that would find favour in Conservative ranks.

But ever since Tony Blair proved the power of pop in politics by embracing the D:Ream song "Things Can Only Get Better", and making it the anthem of New Labour in 1997, British politicians have come to realise the importance of a strong soundtrack. The reggae anthem of Jamaica of the early Seventies is Mr Cameron's first such attempt to rally the faithful.

The power of the rousing political anthem has long been harnessed in the United States, where politicians have unashamedly embraced the idea of musical branding. But the songs are usually far more predictable; so much so that some have come around more than once. Randy Bachman's rock classic "You Ain't Seen Nothing Yet" has been played on the campaign trails of both Ronald Reagan in 1984 and Al Gore in 2000.

But from across the Atlantic comes a warning that campaign songs can be as embarrassing as they are rousing. In 1996 Bob Dole had to stop using his version of the Sam & Dave classic "Soul Man" (which he had adapted as "Dole Man") after the copyright owner sent him a threatening letter.

Jimmy Cliff won't try to stop Team Cameron using his words and music. But whether it will have the same impact in the Home Counties as it had in Jamaica, remains to be seen.