"When there is a one-lane road (such as downtown Clemson) and vehicle traffic is backed up, may a cyclist (legally) skirt around traffic and ride up to the traffic light? If so, do they pass on the right or left of the vehicles?"
A great question. Another bicycle blogger responded that lane splitting, as its commonly called, is not really legal, but sometimes tolerated. So, that being said, I did a little digging myself.
I found this great forum on cyclists from around the world and their opinion or experience with lane splitting. (The forum is a place on the interwebs where I usually get referred to when I'm looking for an opinion or doing other kinds of research.) It would appear that some folks do it provided they feel safe, however, it appears that it's not really legal. So, Heather, it appears that skirting around traffic isn't a good bet. Do not pass on the right, or the left or pass go and collect $200.
But, you ask: Should I give it a try? Again, I would say no. Timing of the lights, unexpected shifts in traffic, unforeseen pedestrians, speed limits. There seems to be many reasons to sit tight and wait your turn in traffic. Not to mention that the folks in their cars aren't going to be too excited when you pass them on your bike just because you can squeeze between them. Especially in a small downtown like Clemson, I'd advise you to hang-tight and wait in line. It'll go over better when you end up next to that car at the next light.
That's the legal, bike-riding advice. However, there are other things you could consider doing. If bike riding is supposed to be a more convenient and fun way to get around, consider taking action in your own community. Contact city commissioners or join (or create!) a local bicycle advocacy group to champion considerations for bicycles. Are the parking spots along the street really the best use of the space or would a dedicated bike lane be better? Is there a need for more or better bicycle parking in your downtown? It might take several months to get the word out and start gathering support, but it's never too late to start.