I chickened out and didn't ask him out. Instead I left my name and number on the back of the receipt. Even though he served me it was the other server behind the bar that took my payment. That could get confusing.
I'm beginning to think I may have been mistaken. It happens all the time so it wouldn't be the first time. I highly doubt I'll get a response, but at least I tried. I'll have to try a little more often and with a little more creativity.