The term 'party lines' refers to a set of political beliefs or opinions shared by a group of people. The crossword solutions for this term are 'TOASTS', 'congas', and 'SLATES'. TOASTS are a form of celebration, usually involving raising a glass and making a speech. Congas are a type of Latin American drum, often used in festive music. SLATES are lists of candidates running for office, usually associated with a particular political party.