Since you'll undoubtedly be making this cocktail all summer long, explore different varieties of sweet vermouth, from old - school classics, like Carpano Antica, to new front - runners, like Lo - Fi. (tastingtable.com)
Combine 1 1/2 cups amber rum (such as Appleton Estate), 1 cup Campari, and 1 cup sweet vermouth in a large pitcher; chill until very cold, at least 2 hours and up to 1 day. (epicurious.com)
But you've really got to like sweet vermouth and Campari to appreciate this drink. (epicurious.com)