MacLean, Bruce Boudreau of the Anaheim Ducks and Joel Quenneville of the Chicago Blackhawks are the three finalists for the Jack Adams Award.
MacLean led the Senators to a playoff berth despite not having defencemen Erik Karlsson and Jared Cowen and top forwards Jason Spezza and Milan Michalek for long stretches during the season.
The 25-17-6 Sens had a league-high 14 rookies make at least one appearance this season.
It's the second nomination for MacLean, who was also a finalist in his rookie season last year.
Boudreau, in his first full season behind the Anaheim bench, led the club to its finest regular season in franchise history, capturing the Pacific Division title and No. 2 seed in the Western Conference with a 30-12-6 record. The Ducks made dramatic gains over 2011-12 in several categories, climbing from 25th to third in the overall standings.
Boudreau also won the award in 2008 when he was behind the Capitals' bench.
Quenneville's Blackhawks posted a record start to the season by earning a point in each of their first 24 games, smashing the NHL's longest previous season-opening streak of 16 games set by the Anaheim Ducks in 2006-07. The club went on to capture the Presidents' Trophy as the league's top regular-season club with a 36-7-5 record for 77 points.
Quenneville captured the Jack Adams Award in 1999-2000 with St. Louis.
Members of the NHL Broadcasters' Association submitted ballots for the award at the conclusion of the regular season. The winner will be announced during the Stanley Cup final.