...played a role in the death of Ilyona Soptic at age 55. The ad features Joe Soptic, 62, of Missouri, who lost his job when GST Steel of Kansas City—owned by Bain and other investors for eight years—was closed. As melancholy music plays, Mr. Soptic says that when the plant closed, he and his family lost their health-care coverage and "a short time after that, my wife became ill." Her illness was diagnosed five years later. "I don't think Mitt Romney understands what he's done to people's lives by closing the plant," Mr. Soptic says in the ad. The steel...