Not a postage stamp. Was the first of a series of gummed labels with portraits of the Presidents of the United States on them that was manufactured by the old HE Harris & Co. They were usually sold (or sometimes included) in album kits to entice kids to learn about stamp collecting. There is also a parallel set of stamps that have the State Flags of the United States on them, too.
I think they still make those US Presidents labels (or at least something close to it) as shown at this web site link:
http://whitman.com/Inventory/Browse...ingPage=trueI remember getting those labels in a collector's kit back when I was a youngster, so your example could be some 20-30 years old by now.