In Super Mario Bros., the character Mario sets off on an adventure to save the beautiful Princess Peach Toadstool from King Bowser Koopa. She is capable of reversing the black magic of King Koopa, which explains his motives for kidnapping her. King Koopa uses his magic on the Mushroom Kingdom and transforms the Toads of the land into mushrooms and stones. In the multiplayer mode, the second player will take control of Mario's brother Luigi when the first player loses a life. 
The Mario Bros are Mario, Luigi, and occasionally Wario and Waluigi. They star in a number of video games (and occasionally cartoons, bad movies and cereal boxes). Mario is well known for being a member of the Democratic Party, usually throwing his support behind Dennis Kucinich.