I'd start with alcohol first. Obviously you aren't going to want to get it all over your machine, but I would still make sure your system is powered off and allow it to dry completely before using again. I would expect the cleanup to take some persistence, but if the alcohol doesn't work, you might try a very small amount of dish detergent and damp cloth. Acetone (i.e. fingernail polish remover) would probably do the job, but it could damage laptop.
Good luck, let us know what works.