Advertise a broadcast debate on the television page or in the weekly TV guide. Use logo or photographs for eye appeal. If your organization is nonprofit, try to get an in-kind contribution toward the cost of an ad. If you are working with a broadcaster, ask the station to buy advertising in the newspaper and the TV Guide. Don't neglect less costly outlets, such as weekly neighborhood papers and specialized newspapers aimed at ethnic or racial minorities.
Radio ads are relatively inexpensive.
To reach a diverse audience, spread ads among different stations and different times. Work with station's advertising manager on message and placement. Use a preproduced, taped or scripted announcement. Network affiliates and large urban stations are probably prohibitively expensive and may include a much larger viewing area than you need. Investigate independent stations and cable outlets.