Possible Clues:

• Promote, in a way
• Piece of lawn sod
• Promotion on a podcast, perhaps
• Favorable word
• Ad, or word that can follow the end of 17-, 26-, 43- or 55-Across
• Wad of tobacco and electrical accessory
• Stopper - connector
• An advertisement for chewing tobacco?
• Device put into socket
• Stopper, advert