The lines in red are indeed spoken. Adelaide is a night-club singer and her troupe of backup singers "talk" those lines. I have the (movie) audio tape and listen to it regularly. Also my mother used to sing this number to us. I agree that Marlon Brando and the Sarah Brown actress were not well cast, but I loved Frank Sinatra as Nathan Detroit, and whoever the woman was who played Adelaide was also perfect. But the most perfect thing is the whole Damon Runyan world, characters like "Nicely Nicely", their 1930s NYC street language, and that terrific song that Adelaide does about how "a poy-son (person) / can develop a cold."