"I was rooting for Donny," she told Access Hollywood guest correspondent La Toya Jackson after the finale on Tuesday night. "He came in every single week and he was so consistent and he worked so hard and he's the nicest guy."
And Kelly said she's got big things in her future, despite not winning the reality competition.
"I'm only 25, I've got the rest of my life to have a big moment and this was his big moment," she said.
Still, her time on "Dancing" has changed her life.
"Oh my God, so much," she said. "I look at everything differently now — before everything was frightening, now everything is exciting. To have that change is just amazing."
Related Content from AccessHollywood.com:
VIEW THE PHOTOS: The 'Fierce' Miss Kelly Osbourne
PLAY IT NOW: Donny Osmond Crowned 'Dancing' Champion (November 24, 2009)
PLAY IT NOW: Can Kelly Osbourne Make A 'Dancing' Comeback? (November 23, 2009)