A group of citizens and others supporting a referendum concerning a proposed YMCA-managed sports complex in Camden said Mayor Jeffrey Graham rebuffed its efforts to turn in signatures connected to a petition seeking the referendum. At issue is whether or not the city should continue with plans to use hospitality tax revenues to construct a regional sports complex and, possibly, enter into a management agreement with the YMCA of Columbia. The initiative’s language asks that a referendum be held as soon as possible so voters’ desires can be established.