Harkin was an attorney before being elected to the United States House of Representatives in 1974, the same year as the other Iowa senator, Chuck Grassley. Harkin served in the House until he was elected to the United States senate in 1984, being reelected every two years. He was reelected to the Senate in 1990, 1996 and 2002. He is noted for his very liberal views. He is particularly interested in issues related to consumers.