My father spent time in Florence, South Carolina, and there they cook their pulled pork in gas-fired metal roasters without any wood smoke. There is a small amount of smoke flavor from the fat dripping on the hot metal, but not enough for me to tell the difference between their barbeque and my pork roast.
That being said, you can take a pork butt, add a generous amount of salt and pepper, and roast it in any electric smoker without wood. It will still tenderize and pull, and have slightly more smoke flavor than you would get in your oven, but not much. Add the vinegar based Carolina sauce and you get a pretty good sandwich, but not the product your smoker was designed to make.