Have Supp. actors from a hit sitcom ever had their own hit?

[RealityChuck]

@RickJay

It might actually be a more interesting exercise to list people who were the stars of popular TV shows without being:

• A supporting actor on any previous show, or
• A successful standup comedian (which eliminates Jerry Seinfeld, Drew Carey, Ray Romano, Brett Butler, Roseanne Barr…)

Assuming one-shot guest appearances as other characters don’t count: Dick Van Dyke, Lucille Ball, Hal Linden, Judd Hirsch (Taxi), Walter Brennan (The Real McCoys), Jason Lee (“My Name is Earl”), David Schwimmer (Friends), Danny Thomas, Ernest Borgning (“McHale’s Navy”), Fred McMurray (“My Three Sons”), Elizabeth Montgomery, to name a few.

[saoirse]

@Annie-Xmas

John Ritter–From Rev. Matthew Fordwick on The Waltons to Jack Tripper on “Three’s Company.”

Wow. The big city sure changed him.

[want2know]

@scotandrsn

Think harder. How about Gavin McLeod from the same show, who went on to star in The Love Boat?

I’ll take you back one step further–Gavin MacLeod had a supporting role on McHale’s Navy years before MTM and Love Boat.

Not a sitcom, but David Letterman was a supporting player on the Starland Vocal Band show.

And, IIRC, Robin Williams was on the attempted Laugh-In revival a couple of years before Mork and Mindy .