Why do the democrats use a donkey as their logo?

Because their donkeys lol lol not really

When Andrew Jackson ran for president in 1828, his opponents tried to label him a "jackass" for his populist views and his slogan, "Let the people rule." Jackson, however, picked up on their name calling and turned it to his own advantage by using the donkey on his campaign posters. During his presidency, the donkey was used to represent Jackson's stubbornness when he vetoed re-chartering the National Bank.

note: i just copied this don't think im an writer or anything