Don Leonard is the Democratic nominee for Ohio's 15th Congressional District in Central Ohio, having won the May 5, 2026 primary with about 53 percent of the vote over former state Rep. Adam Miller. A first-time candidate for Congress, he will face Republican Rep. Mike Carey in the November 3 general election. His campaign has been endorsed by labor unions including AFSCME, SEIU, and the UAW.

The son of a single mother, Leonard grew up knowing times when her resourcefulness and hard work were not enough to keep poverty and homelessness at bay, an experience that taught him the value of personal responsibility as well as safety nets and devoted public school teachers. He describes himself as a "Medicaid kid." He was raised conservative and is today a proud Democrat.

After earning bachelor's and master's degrees from the University of Massachusetts Lowell, Leonard spent two years with the U.S. Peace Corps in South America and went on to earn a Ph.D. in government from Cornell University. He has spent the last ten years as a professor of city and regional planning at The Ohio State University, where his wife also teaches. Their daughter was born in January 2025, and the couple decided they had to do something about the kind of country she would grow up in.