McCoy represented a Northeast Baltimore district from 1975 to 1987, a period of significant change for the city. He also built substantial careers in law, lobbying and business.

"When I think of Denny, I always think of the smile on his face," former U.S. Sen. Ben Cardin recalled. "He was such a nice guy. He was serious about his work, but he always enjoyed being around people."

Born May 26, 1942, McCoy grew up on a small farm in White Marsh but spent most of his life in the Mayfield neighborhood of Northeast Baltimore after marrying the former Carolyn Manieri in 1963. He graduated from Calvert Hall High School in 1960, earned a bachelor's degree in engineering from the University of Maryland in 1965, a law degree from the Mount Vernon School of Law — now the University of Baltimore — in 1968, and an MBA in finance from Loyola University in 1973.

To support his family while studying law, McCoy worked as a state Parole and Probation officer and for a shipbuilding and drydock company. After law school he worked at Hooper, Keifer and Cornell on Charles Street and eventually started his own practice, Polovoy, McCoy and Vincent, later known as Polovoy & McCoy. He spent six years as an appointed commissioner on the state's Criminal Injuries Compensation Board from 1969 to 1975.

At age 32, McCoy was elected to a House seat representing Northeast Baltimore's 44th District in 1974. In Annapolis he was assigned to the House Ways and Means Committee, where Cardin — who chaired the committee at the time — said McCoy threw himself into battles over education funding, working to preserve state funding for Baltimore public schools and other initiatives as the city's population declined.

McCoy went on to spend seven years as chair of the Baltimore City House delegation at a time when the city's power in the State House was waning. Former Del. Tim Maloney, a Prince George's County Democrat, called McCoy "a leader in state support for the city, including the Inner Harbor redevelopment and aid to education," who used his Ways and Means post to advocate for Baltimore.

"The Baltimore City delegation could be a fractious group, and Denny had an excellent way of building consensus, easing tensions, and creating unity from very diverse sections of the city," Maloney said.

Former colleagues said McCoy helped smooth relations between political factions and served as an ambassador to other neighborhoods as Baltimore's legislative districts were forced to consolidate amid population loss.

"The tensions pretty much dissipated" thanks to McCoy's work, said former Del. Maggie McIntosh, a Baltimore City Democrat who went on to become House majority leader and chair of two House committees. While McCoy was "rooted in his community," she said, he had an ability to see and understand what was happening politically in surrounding areas.

After leaving the legislature in 1987, McCoy founded a lobbying practice, Government Affairs-Maryland Inc., and became one of the top-earning lobbyists in Annapolis. He helped win repeal of many of Maryland's blue laws and was passionate about representing the Maryland Horsebreeders' Association, which he believed was an important part of the state's culture, tradition and history.

McCoy's daughter, Kimberly McCoy Burns, also an attorney, joined his firm and lobbied alongside him in Annapolis for 25 years. "My Dad definitely left the world — or at least Maryland — better than when he found it for so many," she said. "He was a compassionate leader, a fierce advocate, and a wonderful father."

McIntosh described McCoy as notably even-keeled throughout his career as a lawmaker and lobbyist.

"When he approached you as a delegate, he was thoughtful, he listened, he solicited your ideas. He was never flamboyant or robust or over the top," she said. "As a lobbyist, he came in the same way. He was never flamboyant or over the top."

McCoy later served three years as CEO of Mars Super Markets Inc. He retired from practicing law and lobbying in 2016.

His wife of 47 years, Carolyn, died in 2010.

In addition to his daughter, McCoy is survived by a son, Dr. Dennis C. McCoy Jr.; son-in-law Michael W. Burns; three grandchildren; his brother Timothy and sister Pam; his companion, Elizabeth Smith Anderson; and several nieces, nephews and cousins.

Visitation will be held Wednesday, Nov. 11, from 2 to 4 p.m. and 6 to 8 p.m. at Barranco Severna Park Funeral Home and Cremation Care in Severna Park. A memorial mass will be celebrated Thursday, Nov. 12, at 10:30 a.m. at Our Lady of the Fields Roman Catholic Church in Millersville.