THE massive swing achieved by the Liberal Democrats in the Bromley and Chislehurst by-election was another classic illustration of the sophistication of the party’s by-election machine.

In the smart suburban streets and leafy lanes of this commuter belt seat on the South London-Kent borders, the Lib Dems fought a ruthlessly effective propaganda campaign to come within 700 votes of a major upset.

Their electoral black arts left the Conservatives floundering as Sir Menzies Campbell, the Lib Dem leader derided as too old and ineffectual, celebrated at David Cameron’s expense. Sir Menzies made three visits, one a week, and courted the local press, while Mr Cameron visited just once and barely featured in Tory by-election material.

The Liberal Democrats' strategy was not complicated: they devised one, simple by-election message and repeated it again and again.

But it was only a series of errors by the Conservatives that provided them with that message after local Tories in the constituency rejected candidates from Mr Cameron’s A-list of candidates to chose their own man.

The moment Bob Neill was selected as the Tory candidate, the Lib Dems saw their chance. He was already an elected member of the Greater London Assembly, where he was Tory leader, and declared that he would serve the remainder of his term until spring 2008 if elected to the Commons. He was also a part-time barrister and a non-executive director of North East London strategic health authority.

The Lib Dems branded him"three jobs Bob" - and repeated the tag on every piece of by-election literature. They highlighted mercilessly the fact that Mr Neill lived in the Isle of Dogs rather than in the constituency, and portrayed‘EastEnder Bob’ as a professional politician and outsider.

Having settled on their message, the Lib Dems used their particular strength to disseminate it: hundreds of thousands of leaflets were delivered by an army of volunteers who flooded to Bromley and Chislehurst from all quarters of the country. In the final days of the campaign the Lib Dem headquarters on Bromley’s main shopping street was thronging with Lib Dem leafleteers.

Residents, and even rival political parties, marvelled at the volume of Lib Dem literature delivered in such a short space of time: skilfully designed tabloid newspapers, glossy brochures, newsletters, even a magazine style compendium including pictures of their candidate Ben Abbotts as a baby. This last publication had a mock Post-it note on the cover as though delivered from a friend or well-wisher.

Although it was a short campaign, voters in Bromley and Chislehurst quickly fastened on to the Lib Dem message. Even rival candidates started to repeat the same message in their own literature and comments to the local press.

The Conservatives cried foul, protesting that their candidate was the victim of negative campaigning.
Their own literature was positive, resolutely focused on local issues such as crime and over-development and concentrated on projecting Mr Neill - the man everyone by now thought of as"Three Jobs Bob" - as a local champion.

The strength of traditional Conservative support in the area presented a formidable challenge to the Lib Dems: Eric Forth, the previous Tory MP who died last month from cancer, polled 51.1 per cent of the vote in the general election last year for a majority of 13,342. Tory councillors did even better in the local election last May, winning every council seat in the constituency.

To overcome this, the Lib Dems even formed an unholy alliance with the UK Independence Party, whose MEP Nigel Farage lives in the area and fought the seat.

Conscious that the UKIP could bite chunks from the Tory vote that they could not, the Lib Dems alerted the UKIP to a legal question mark over Bob Neill’s eligibility to serve as an MP as his directorship of a health authority was a public office under legislation from 1975 banning MPs from conflicts on interest by working for public bodies.

The UKIP sought legal advice amid more local protests at Mr Neill’s suitability as a candidate. The story was taken by the Bromley Times, whose front page story on polling day yesterday reported the theoretical risk of the by-election being re-run if Mr Neill won.

It was not the sort of headline that any candidate would want to face on polling day. The Conservatives might cry foul - but by the time they did, it was too late.

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