Dan - Its a new boat, how far from your dealer are you? I'm sure they will fix it licketysplit!
I had the same boat as Mike L, I never had the leak he had (I think I remember his rear livewell line froze with water in it) but I did have Tracker shorten the drain tube so it would drain better and not hold water, but we don't get the cold down here and mine lived in the garage when ever it was not on the water.
I'd say if the plug was in (don't laugh, we've all done it and i've met folks at the ramp who didn't KNOW there was a plug!!! LOL), then chances are its a fitting loose/broke in transit from the factory.
One way to check, is to fill up the livewell and PLUG the rear livewell DRAIN hole on the bottom of the transom, and wait a bit at home and see if the water drains from the livewell into the bildge.