Broadcast service is an integral part of wireless networks, through which important control and signaling information are typically exchanged. However, its multi-receiver nature determines that broadcast suffers more from access collision and hidden node problem. In wireless ad hoc networks, the phenomenon becomes even worse due to the absence of a central coordinator. Existing media access control (MAC) protocols in wireless ad hoc networks were primarily designed for unicast service and the potential broadcast support is not satisfying. In this paper, we introduce a MAC layer protocol, namely Parallel Signaling and Persistently Synchronous MAC (PS 2 MAC) that can significantly alleviate both access collision and hidden node problem. A novel relay technique is deployed in PS 2 MAC so that a superior broadcast performance, such as throughput and packet delivery ratio, is achieved. The conclusion is supported with simulation analysis.