Dungy and Harrison are two of the 15 finalists for this year's Hall of Fame class.
The 46-person Hall of Fame panel will vote for the 2014 class on Feb. 1.
Dungy, the winningest coach in Colts history, won five division titles, reached the AFC Championship Game twice and won a Super Bowl while coaching the team from 2002-08.
Harrison was second in league history in receptions when he retired in 2008. He had eight straight 1,000-yard receiving seasons. He ended his career with 1,102 receptions for 14,580 yards and 128 touchdowns.
The Colts have 12 individuals in the Hall of Fame.