Stir wine and sugar together, set aside for 10 minutes.
Stir water and Certo together and then stir into wine mixture. Stir constantly for 3 minutes, then fill jelly jars to within 1/2" of tops.
Wipe tops of jars and cover with lids.
Let stand for 24 hours at room temperature, then freeze. Store in refrigerator after opening.
Use any red, rose or white wine. Or use a cream sherry, white port or marsala.
Sweet wines make a more flavorful jelly than dry wines do.
Tip: I have found this works best if you heat the wine and sugar while stirring. I couldn't get the sugar to dissolve until I did. I also filled the jars with hot water while making the jelly so they were warm when I filled them. This seemed to help the lids seal better.