Try Goo Gone. You can get it at WalMart. Let it sit for a few minutes and wipe. It will remove all kinds of gunk including overspray. Of course, you should wash the vehicle afterwards and then rewax.
I have seen a lot of recommendations in this thread for pine sap removal. Perhaps they work, but the one thing I have always used and has never, ever failed, is acetone. (nail polish remover). 100% success. And if there is a female in your house, it will always be available.