The activity helped to improve turnout by 2% over 2001 figures, to 61%.
The election saw the adoption of US-style campaigning, using sophisticated databases, market research, telemarketing and other direct marketing techniques to deliver targeted messages to floating voters, as predicted by Marketing.
Direct mail and door-drops accounted for almost £4.4m of the £17.8m spent by the Conservative Party, 269% up on the sum spent in 2001. It spent £8.2m on advertising.
Labour boosted its direct spend by 86% to £2.7m and market research by 81% to £1.6m. Its adspend crept up 5% to £5.3m, out of a total of £17.9m.
The Liberal Democrats spent £1.23m, 29% of its budget, on direct methods.
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