It is thought that the Wizard of Oz symbolizes either President William McKinley, or Mark Hanna. In the story the Tin Man, Scarecrow and Dorothy all see the Wizard differently. This is similar to how politicians are seen differently by the citizens, and the cynicism that exists in politics.
(To the bottom right) This is Mark Hanna, republican senator of Ohio. He was the political manager of President William McKinley. Hanna was a millionaire and used his money in campaigns for William McKinley.
(To the top right) This is President William McKinley, who served the country from March 4, 1869 to when he was assassinated in 1901
The Yellow Brick Road
The yellow brick road, pictured throughout the film, is also a symbol of the Populist and Progressive parties. It symbolizes the gold standard that William McKinley wanted, and it leads to power (the Emerald City)
(To the left) This is the yellow brick road that is a prominent part of the main characters' journey to Emerald city.
(To the right) This is a picture of Gold, the currency standard that William McKinley wanted to use instead of Silver.
The Munchkins
The Munchkins, the people that populate much of Oz and greet Dorothy after the Twister, are said to represent the people that were practically enslaved by factory owners, or common american citizens. The Lollipop Guild is supposed to represent child labor that was present at that time.
(To the left) This is a picture of the Munchkins, a group of little people that lived in the Land of Oz.
(To the right) This is a picture of a young girl in a cotton mill, a victim of child labor.
The Ruby Slippers
The Ruby Slippers first appear on the Wicked Witch of the East, and then Glinda gives them to Dorothy. This is a great difference from the book. In the book the slippers are silver. This symbolizes that the silver standard that the farmers wanted.
(To the left) This is an image of the Ruby Slippers right after Glinda gives them to Dorothy.
(To the right) This is an image of the silver standard.
The Cowardly Lion
The Cowardly Lion represents William Jennings Bryan. The Cowardly Lion has a loud roar, but no bite; this is similar to how William Jennings Bryan had no power, but a strong voice.
(To the Left) This is the Cowardly Lion, one of the main characters of the Wizard of Oz.
(To the right) This is William Jennings Bryan, a late 1800's politician.