Place your soda in a saucepan over medium-high heat. Keep the soda on the stove until it boils. Boiling times will vary, but most liquids boil within a few minutes. Once your soda is boiling, immediately transfer it to a medium-sized mixing bowl. Sprinkle your gelatin over the soda and stir gently until it dissolves completely. When dissolved, you will no longer be able to see the gelatin mixed into the soda. Times vary, but gelatin usually dissolves within a few minutes. Pouring the wine straight into the boiling gelatin mixture will cause the alcohol to evaporate. Give the mixture a few minutes to cool down first. Once the gelatin is dissolved, pour your red wine into the gelatin/soda mixture. Stir until the ingredients are combined. You can use a turkey baster or a container with a spout to distribute the mixture between your shot glasses. Fill each glass just to the brim with the mixture. Place your shots in the fridge. Chill them for a few hours or overnight until the shots are set. Times will vary, but most shots will set within 24 hours. You can remove your shots by running a knife along the side of the shot glass. You can also simply have guests remove the shots themselves at a party or get together.

Summary:
Boil your soda. Mix your soda and gelatin. Let the mixture cool for a few minutes. Add your red wine. Pour your mixture into your shot glasses. Refrigerate your shots overnight. Serve your shots.