This wintry, ruby-red spin on sangría is a staff favorite but comes with a warning: It goes down easy. Make it a day ahead, and add the Champagne right before serving.
Combine cranberries, sugar, and water in a medium saucepan over medium-high; bring to a boil, stirring often until sugar dissolves and berries just begin to pop, about 3 to 4 minutes. Remove from heat; cool 30 minutes.
Stir together sangría, Campari, and cooled cranberries with liquid in a large pitcher or a small punch bowl. Add orange and apple slices. Just before serving, add Champagne.
Serve over ice with a few pieces of fruit in each glass.