Combine popcorn and golden raisins in a large bowl.
Bring sugar, water, corn syrup, salt, and vinegar to a boil in a saucepan, stirring until sugar has dissolved. Clip a candy thermometer to side of pan, and continue to cook, without stirring, until mixture reaches 290 degrees, about 14 minutes.
Pour hot syrup over popcorn mixture, and stir until well coated. Working quickly, shape mixture into 2 1/2-inch balls, and transfer to parchment to cool.
Popcorn balls can be stored in an airtight container for up to 2 days.
This recipe is very good, but I have noticed that almost all recipes for popcorn balls follow one of two formulas, so I simplified them: You can use this recipe with a 1/2 cup of any add ins you like instead of raisins plus a few drops of food coloring if you like, or you can use this other one http://www.marthastewart.com/339167/popcorn-balls with 1 cup of add ins and whatever food coloring you like.