CHICAGO, Feb 12 - The U.S. retail sector may have stagnated in January amid soft automobile sales, but spending in some areas was buoyant, helped by redemption of holiday gift cards. A poll shows a median forecast for sales to be unchanged in January from December, when sales rose 0.5 percent. The 26 estimates ranged from down 0.5 percent to up 0.8 percent. Excluding autos, sales were forecast up 0.5 percent after rising 0.1 percent in December. The U.S. Department of Commerce releases its retail sales data on Thursday at 8:30 a.m. EST (1330 GMT).//