Ours Go to 11: Volume 5, My Favorite Supporting Characters on Sitcoms

Sometimes hard to define, especially in the case of some ensemble casts, but whoever you think is apt can be eligible. 

1. George, Seinfeld (Jason Alexander)
2. Norm, Cheers (George Wendt)
3. Jim, Taxi (Christopher Lloyd)
4. Lenny & Squiggy, Laverne & Shirley (Michael McKean and David Lander)
5. Norton, The Honeymooners (Art Carney)
6. Louie, Taxi (Danny De Vito)
7. Elaine, Seinfeld (Julia Louis-Dreyfus)
8. Radar, M*A*S*H (Gary Burghoff)
9. Ted Baxter, The Mary Tyler Moore Show (Ted Knight)
10. Phoebe, Friends (Lisa Kudrow)
11. Mike, All in the Family (Rob Reiner)

Plus a few more
Carla, Cheers (Rhea Perlman)
Kramer, Seinfeld (Michael Richards)
Alice, The Brady Bunch (Ann B. Davis)

Latka, Taxi (Andy Kaufman)

George, Newhart (Tom Poston)