Personalized electronic content is generated for display on a user computer. The content is generated by first matching a targeted user online identifier to one of a plurality of user online identifiers associated with a master ID in a database. Using online user behavior associated with the user online identifiers of the master ID, a preliminary set of personalized electronic content is generated. A set of content usage parameters is applied to the preliminary set of personalized electronic content to define the personalized electronic content, which is then transmitted and displayed on a user computer. The personalized electronic content may comprise targeted advertisement utilized to populate a webpage or an email template defined by an online marketing campaign.