Goo Gone, or mineral spirits, or even lighter fluid to loosen/soften it up.
Use the above and "mechanically clean" or scrape the residue off.
Those bamboo kitchen skewers are great for that, they are a little thicker than a toothpick and about 12 inches long.
But don't use metal to scrape! Metal will scratch.
Stick to bamboo or wood.
Those Bamboo skewers are usually a buck a pack (pack of 50) in a dollar store.
They are also great for picking lint/dirt/etc out of the innards of folding knives.
You can whittle them down to fit in really tight hard to reach spots.