Place warm water, margarine, honey, bread flour, oat bran, salt, and yeast into a bread machine in the order listed, or follow the order recommended by your manufacturer if different.

Run the Dough cycle.

After dough has risen once, remove it from the machine. Knead dough a few times, then shape into a loaf. Place into a greased 9x5-inch loaf pan and let rise until doubled in size, about 1 hour.

Preheat the oven to 350 degrees F (175 degrees C).

Bake in the preheated oven until done, 35 to 40 minutes, or until done.