Presidential campaigns often are defined by their symbols, visual images that are more powerful than thousands of words.
Supporters of Andrew Jackson, Ole Hickory, erected poles made from hickory across the country. William Henry Harrison used the log cabin image to good effect while Abe Lincoln backers carried axes to symbolize his rail-splitting days.
The donkey as a symbol of the Democratic Party was begun derisively by opponents of Andrew Jackson in 1828 but Jackson successfully turned it into a positive image of dogged stubbornness. The Republican elephant started life as an image in an 1874 Thomas Nast political cartoon and stuck.
Sometimes the image that defines a campaign is negative and created by the campaign it undermines. Consider the photo of Michael Dukakis riding a tank. Whatever the intent, the result made Dukakis look small and impotent. He never escaped that image.
Now we get to the Etch-a-Sketch. It has all the makings of a permanent symbol. It is simple, memorable, and has elements of truthiness in it. I wouldn't be surprised if Etch-a-Sketches show up at every Romney rally from now until November.
I also would not be surprised if the Romney campaign right now has agents spread out across the country buying up and destroying every Etch-a-Sketch in every toy store in America.