Beat first five ingredients at high speed with an electric mixer for 3 minutes. Pour half of batter evenly into 2 greased and floured 8 x 3 loaf pans.
Stir together sugar and cinnamon; sprinkle half of sugar mixture evenly over batter in loaf pans. Pour remaining batter evenly into loaf pans, and sprinkle with remaining sugar mixture. Gently swirl with a knife.
Bake at 350° for 45 minutes or until a wooden pick inserted in center comes out clean. Cool in pans on wire racks.