I'm sorry about your little plant. I've had VC for a few years and it's very tough. I think the plant might have been doomed when you brought it home because of improper care from Lowe's. It sounds like root or stem rot.Don't be tempted to keep it moist or it will surely die. Try taking a small cutting from the top 3' or so or take it back to Lowe's.
Best of luck-Debbie

I have found that Vancouver Centennial really does not like full sun. But I have overwintered it in a west window before. If the sunlight in the afternoon is really intense and hot I think that could be the cause of wilting. Try a location with a little more less intense light.

Out of curiousity, how tall have your Vancouver Centennial geraniums been? I got one late fall, and its still blooming, but I am wondering if I need to put it in a larger pot....

Thanks for the help!