First, to avoid definitional problems, I'm willing to include anything that has some sort of broth and is eaten from a bowl, whether as an entree (pho, menudo, cioppino) or as a separate course. If it's served in a bowl, but transfered to a plate before eating, or if it doesn't have something liquid enough to count as broth, then it's a stew, and doesn't count. Chili counts, no matter how thick it may be. Other than that, consider the field wide open to all styles and ethnic origins.
Also, given that this thread may become one that will be found in the future by people searching for a general guide to the best available, rather than a commentary on any one soup at any one place, try to put the geographic location of your nomination toward the front of your post, such as "Baltimore - the Fish Tea at Ras Doobie's..." followed by your description of the dish itself, why you like it, or whatever else you're going to say.