Donkey first used as symbol of Democratic Party, in Harper's Weekly
Snippet of Article: "...While not the official logo of the US Democratic Party, the donkey is the most common.
Andrew Jackson's opponents called him "jackass" as a play on his name and as a term of ridicule regarding a stupid and stubborn animal such as a donkey. The Democrats however liked the common-man implications and began to use the symbol in campaign posters. ..."