U.S. ports from Maine to Texas could shut down Tuesday if a union representing about 45,000 dockworkers carries through with a threatened strike. A lengthy shutdown could raise prices on goods around the country and potentially cause shortages and price increases at big and small retailers alike as the holiday shopping season — along with a tight presidential election —

With a potential strike at ports up and down the East Coast and along the Gulf Coast set to begin after midnight Monday, logistics executives tell CNBC the remaining hours are critical in moving out as much trade as possible before a shutdown that will do serious damage to the functioning of the U.S. economy.