Media theory helps the process of understanding the complex political communication environment. Agenda-setting research examines the transfer of topic salience from the media agenda to the public agenda. This process is important to discuss in the policy context of election campaigns. In an election campaign context, agenda-setting has been altered considerably since its early research studies by the technology that allows individuals and organizations to use social media to communicate directly to an audience and by the campaign finance structure created by the Citizens United ruling with money that provides for greater message exposure through advertising serving as an agenda-setter.