With only a limited spend on press and poster advertising, the campaign teams devoted much of their energies to their four party election broadcasts.
Audience figures from Barb for the first two spots, disclosed to the parties this week, suggest the Tories won a better response from the voters than Labour.
The Tories' first broadcast won an average audience of 10.5 million and the number of viewers rose by three million during it. Its second film won ten million and gained 750,000 viewers while on the air.
Labour's first two slots both won an average of nine million viewers, with the first gaining 1.2 million and the second losing 300,000. Labour, which has been accused of running a negative campaign, featured the Tory leader, Michael Howard, in all four of its broadcasts as it attacked his record as a minister in previous governments. In contrast, Tony Blair did not appear once.
The Tory broadcasts were made by The Bank, which makes corporate videos for clients including Sony and Shell, in its first foray into politics.
The party also tried out two agencies, Immediate Sales and VCCP, in a dry run for the general election expected in May next year.
The Tories spent more heavily in the regional press than at previous elections, partly in response to the use of all-postal ballots in four regions - the North West, the North East, Yorkshire and Humberside and the East Midlands. They ran one burst in these areas when ballot papers were sent out and another in other regions this week. The shift towards regional spending is likely to be repeated at the general election, when postal voting is expected to be extended.
Tory sources say the party will take a decision on whether to appoint a single agency for the general election or rely on a team approach after analysing the current campaign.
Labour officials said they were delighted with the performance of TBWA\London and said valuable experience had been gained for the general election, for which the agency would be retained.
The Tories have also invited agencies and individuals to respond to an open brief calling for work to run as part of its "Let down by Labour" advertising activity.