Techniques are described for promoting content items in a page to load in a different order than the order in which they were initially designated to load in the page source. A page may include critical content items designated to load earlier than non-critical content items. In instances where there is a delay due to latency in generating or retrieving the critical content items, one or more non-critical content items may be promoted to be sent earlier than initially designated. Promotion may include packet reordering, such that packets including non-critical content items are sent to a user device prior to the packets that include critical content items. By promoting non-critical content items to be sent during the period in which the loading of the page may otherwise be stalled, overall page load times may be reduced.