Robert Dayton, a scion of the department store family and downtown Minneapolis civic booster, has died of complications from pneumonia in Naples, Fla.

Dayton, 73, was a great-grandson of Dayton’s Department Store founder George Draper Dayton and one of 16 first cousins to Gov. Mark Dayton. He spent a career in the family business both at Dayton’s and at Harold.

“Bob was like my big brother growing up, and we have been good friends for life,” Gov. Dayton said in a statement. “We had many spirited political discussions, but they were always warmhearted. For us, blood was always thicker than politics.”

After graduating from Yale in 1964, Robert Dayton started his retail career in the women’s shoe department at Dayton’s, eventually rising in the company to become general merchandise manager and vice president of stores.

With a passion for merchandising, Dayton had an eye for identifying and supporting designers early in their careers, including Ralph Lauren and Calvin Klein.

“He had such charisma and usually had a smile on his face,” said Mary Hughes, the divisional manager of the Oval Room at the time. “He was sarcastic to the guys and darling to the women. He was a dear friend.”

In 1977, he left Dayton’s and purchased the upscale women’s department store Harold downtown. “Harold was the ultimate fancy store in Minneapolis,” said former Secretary of State Joan Growe. “It was the place to shop for a special occasion. My mother and I went there to shop for something after I was first elected secretary of state.”

In 1984, Dayton pushed the development of the Conservatory on Nicollet Mall, an enclosed downtown mall that went against the trend of suburban malls. Criticized for being dark and labyrinthine, the effort was deemed a failure, shuttered and razed. The U.S. Bank headquarters building eventually replaced it.

Dayton’s charitable contributions included founding Mentoring Partnership of Minnesota in 1996, which supports a network of mentoring programs for youths and families. He met with local CEOs, including 3M and General Mills, to start funding the program.

“Bob was a silent leader but with a big heart,” said Mai-Anh Kapanke, executive director at MPM in Minneapolis. “He believed that every young person should have support systems to find their spark.” The charity helps more than 176,000 youths statewide annually, according to Kapanke.

He was also committed to local nonprofits including the Guthrie, the YMCA and the Minneapolis Institute of Art.

Dayton also served as chairman of the Downtown Council, advocating to bring the Super Bowl to the Metrodome, keep the Minnesota Timberwolves in town and build a new ballpark for the Minnesota Twins.

Dayton, whose father Donald was a brother to Bruce and Kenneth Dayton, is survived by his wife Joan Layng Dayton, brothers Edward of Florida and John of Dallas, and sons James, a Minneapolis architect, Scott, who owns Twill menswear in the Galleria, and Tobin of Wayzata.

Dayton died Sunday. Services are pending.