The acquisitions follow a series of revelations by The Daily Telegraph detailing MPs' claims, which have generated widespread public anger.
The party has bought the phrase 'mps expenses'. Those entering this phrase or similar search terms into Google will be offered a sponsored link to David Cameron's Webcameron channel on YouTube. Here they can watch a video in which the Tory leader explains the expenses rules he has put in place for MPs from his party.
Jeremy Hunt, the Conservative Party's spokesman for online campaigning, said: `It is important for us to lead on the issue of MPs' expenses and reassure the public, who are rightly angry about everything that's happened, that we are taking immediate action to clamp down on abuses of the system.
'Our Google pay-per-click campaign directs everyone searching for key words and phrases on the issue to a Webcameron video where David explains exactly the measures he is taking to sort the system out,' added Hunt.