During my time in radio, I wasn't involved with all that many contests. Thus, when I got to give away a CD, I treated it like a tightrope walk. Typically, I would talk at least twice as fast as I usually do. Occasionally, a caller would say, "Oh, I'm caller three? I didn't even know there was a contest. I actually just called to request a song..."
If that caller wasn't the designated winner, I'd usually say something like, "OK,I'llplayitsoon,Thanks...," without pausing between words.
It was always important to me to announce the winner's name on the air or say, "We have a winner," on-air as soon as possible. Looking back, it wasn't necessary to sound so hyped up. I wasn't giving away millions of dollars in a lottery, after all. Still, there's something about a contest that triggers reflexive excitement in a DJ, I think.