Heat the olive oil in a Dutch oven or large pot over medium heat. Add the onion, celery, parsley, garlic and crushed red pepper flakes. Cook, stirring occasionally, until the vegetables are very tender, about 15 minutes. Increase heat to medium-high and add the wine and cook for about a minute. Add oregano and bay leaves and cook for 30 seconds. Add 2 cups clam juice (or stock) and canned tomatoes and bring to a boil over high heat. Reduce heat to a simmer and cook until slightly thickened, 20 minutes.