After taking office in his hometown at the age of 29 — making him the youngest mayor of a U.S. city with at least 100,000 residents — he confronted an industrial Midwest town that, like many others, had been left floundering by economic changes in recent decades that ruined much of the city's financial base. He pushed to revitalize South Bend, draw in new residents and businesses, diversify the economy and clean up blighted homes.