I made a diagram of field marks for Clay-colored Sparrow to help separate from Chipping Sparrows. I photographed this Clay-colored Sparrow on a recent trip to Wilmington. It was feeding in the grass beside the parking lot of the NC Aquarium. October 18th, 2014. (notice the new logo in the upper right corner?). *Also Juvenile Chipping Sparrows is another similar plumage similar looking to winter adult. Other diagrams of Chipping Sparrow diagrams.
Photo of sparrow taken off google images, not mine.