I saw "lamp style" votive holders at the Dollar Tree just yesterday (here in Buffalo). Just clear glass "stem" so they're about 6-8 inches tall, then the votive sits in a "cup" at the top, and there is a clear glass "shade" over the top. I hope that explains it well enough to you. I thought about buying several for centerpieces myself! I am just leary to transport so much glass....
Also, those battery operated ones can be bought in quantity online. You'd have to search it, but I found them for my church (we use them in the choir). I can't remember where I got them. However, they are like tapers -- tall and thin, not wide like pillars. I do agree that it could give you a nice effect (from a distance) without the danger of open flames. Definitely consider it. Oh, and the ones we bought have a removable brass stand so they can stand all by themselves!!! Tighten the bulb to turn them on, loosen it to turn them off.
Good luck!