By Brad Dorfman

(Reuters) – U.S. retail sales should rise 4.1 percent this holiday season, slower growth than in the past two years as mixed economic data and political uncertainty weigh on consumers, the world’s largest retail trade association said.

The forecast released on Tuesday by the National Retail Federation puts sales at $586.1 billion in November and December. The 4.1 percent growth forecast trails the 5.6 percent growth seen in 2011 and 5.5 percent growth in 2010.