The Tories' first election broadcast pulled in a viewing audience of over 12 million - more than Labour's advert featuring Tony Blair and Gordon Brown.
The two adverts were broadcast across the five terrestrial channels at different times on Monday and Tuesday.
The Conservative broadcast, focusing on Michael Howard's leadership, attracted a total audience of 12.8m, while Labour's drew in 11.9m.
The Lib Dems' first election broadcast will be screened on Wednesday evening.
The Tory ad attracted an audience of 9.9m, or 55.2% of the number of people watching TV at the time, when it was simulcast on BBC1 and ITV1 at 1845 BST on Tuesday.
Some 4.6m, or 25.6%, of the available audience watched it on BBC1, ahead of Watchdog, while 5.3m, or 29.6%, watched it on ITV1 before the soap Emmerdale.
On BBC2, the ad attracted 1.6m people, or 10.5% of the total audience at 1745 BST.
When it was shown on Channel 5 at 1915 BST, it drew in 400,000 people or 1.9%, of the available audience, while at 1945 on Channel 4, it attracted 900,000 viewers or 4.1%.
Labour's four-minute advert shows Mr Blair and Mr Brown discussing how they reformed the party together.
It was produced by Oscar-winning film director Anthony Minghella, whose credits include The English Patient and Truly, Madly Deeply.
An audience of 9.6m, or 52.4% of the number of people watching TV at the time, saw the advert when it was simulcast on BBC1 and ITV1 at 1845 on Monday.
Some 4m people, or 21.8% of the available audience, watched it on BBC1, between the news and Holiday 2005.
The other 5.6m, or 30.6% of the total audience, watched it on ITV1, ahead of Emmerdale.
On BBC2 the ad followed the Weakest Link and attracted 1.6m viewers, or 10.9% of those watching.
It was later broadcast on Channel 5 at 1915 BST, drawing in 0.2m people, or 1% of the available viewing audience.
The ad was then seen by 500,000 people, or 2.3% of the total audience, at 1945 on Channel 4.