I noticed that I must have gotten some glue on a piece of wood I'm finishing since it doesn't take stain in the form of
a drip run...

Is there any way to fix this besides sanding it all again?

Is there a way to prevent this? If I do notice some glue on a good surface, how should I take care of it? I've been
using a wet rag... does that get it all?

I use regular white or yellow wood glue.

Thanks