At least one aspect of the present disclosure is directed to systems and methods of selecting and acknowledging content to broadcast. A system can receive, at a first time, a request for content to broadcast identifying a content publisher. The system can obtain cluster data of the content publisher corresponding to a first time, the cluster data identifying content selection metrics based on predicted characteristics of the cluster corresponding to the first time. The system can determine a subset of content items having cluster filtering criteria that satisfy the content selection metrics. The system can rank the subset of content items based on the content selection metrics to create an ordered list of content items. The system can transmit data identifying the order of the content items to the content publisher. The content publisher can insert the content into a broadcast in the order identified by the system.