1. A computer-implemented method for selecting a target audience for a marketing campaign using a graphical user interface, the method comprising: creating, in a first window on a display device of a computer, a graphical representation of an initial audience profile, wherein: the initial audience profile comprises a first number of content records, a content record representing a potential target for a marketing campaign, and the graphical representation of the initial audience profile indicates the first number of contact records; presenting, in a second window on the display device of the computer, graphical representations of data attributes, wherein: a data attribute represents a valid entry in a contact record; receiving a first user input that represents a selection of a graphical representation of a data attribute presented in the second window; after receiving the first user input, presenting an action area in the first window of the display device of the computer, wherein the action area represents an operation that can be performed on the initial audience profile using the selected data attribute; receiving a second user input that represents a selection of the presented action area; performing the operation represented by the selected action area on the initial audience profile using the selected data attribute to determine an updated audience profile that comprises a second number of content records; and presenting, in the first window of the display device of the computer, a graphical representation of the updated audience profile that indicates the second number of content records.