This is a hard one to deal with because the range of dyes and other ingredients used in carbonated drink is massive and changes all the time.
As a starting point, on polyprop I would use ultra pack renovate, then a cool water rinse, this may or may not remove the stain but will serve to remove some components and dirt adhered to the sugar content.
From there, there are many chems but i prefere Prochem Red R ex. Use it in dab/blot style first, dwell and rinse hot and if the response is limited, it can be used in thermal transfer method,but be carful as heat can totally set the stain and dont get the heat too hot as your dealing with a plastic.
As to the other treatments, there are others that may work, some that I would not like to say on line as the eyes will roll :
, also pop dyes some times respond to rust treatments as a last resort.
Glad im only on my first glass of wine