A 1962 graduate of Snyder High School, Marcum played quarterback at McMurry University under head coach Grant Teaff. He was a 2001 inductee into the McMurry University Athletic Hall of Honor.

He landed his first collegiate coaching job at Ranger College, and, in 1979 guided the school to the Junior College National Championship.

He began his Arena Football League Career in 1987 as head coach of the Denver Dynamite. Marcum is the winningest head coach in Arena Football history. He has won seven ArenaBowl championships and is the only coach in Arena Football History to lead three different teams to ArenaBowl championships.

Tim Marcum was the first coach in pro football history to be elected to any professional Hall of Fame while still an active coach.

In 2004 he was the first recipient of the American Football Coaches Association’s Outstanding Achievement Award.

He is currently the head coach of the Tampa Bay Storm.