In 1977, Kucinich became the Mayor of Cleveland. At the time, Kucinich was the youngest person ever elected to lead a major American city. In addition to being Mayor of Cleveland, Kucinich has served as a Council Member for the City of Cleveland (1970-75, 1981-82), as the Clerk of Courts for the Cleveland Municipal Court (1976-77) and as an Ohio State Senator (1994-96).

In 1996, Kucinich was elected to the U.S. House of Representatives. As a Congressman, Kucinich has been a progressive proponent of environmental initiatives, sustainability practices, human rights issues and the social and economic interests of his Ohio constituents, including the troubled steel industry. In 2001-2003 Kucinich was Chairman, and later Co-Chairman (2004), of the Congressional Progressive Caucus.

Kucinich is known for his idealism, activism and indefatigable spirit. In 2003, Kucinich began his campaign for the 2004 Democratic presidential nomination with a platform largely dominated by human rights and environmental initiatives. In his campaign for the 2008 presidential nomination, he called for universal healthcare and an immediate withdraw from Iraq. In 2007 and 2008, he introduced impeachment articles for Vice President Dick Cheney and President Bush respectively

Kucinich is the chairman of the Domestic Policy Subcommittee of the Oversight and Government Reform Committee. He is also a member of the Education and Labor Committee. In November 2008, Dennis Kucinich was reelected to a seventh term in Congress.