21. The method of claim 12 , wherein the target is a search query communicated to a search engine by an Internet user and each of the plurality of candidates is an advertising message with a corresponding advertising message categorization vector.
21. The method of claim 12 , wherein the target is a search query communicated to a search engine by an Internet user and each of the plurality of candidates is an advertising message with a corresponding advertising message categorization vector. 22. The method of claim 21 , further comprising displaying the original search results with one or more advertising messages selected based on a comparison among the distances between the advertising message categorization vectors and the target categorization vector.