It's a little early to know for sure- the bird in question doesn't appear to be fully feathered out yet. But my guess at this point is cockerel based on the larger comb. You should know soon-- if that comb keeps growing and turns red in the next few weeks, then it is probably a cockerel. Also watch the wattles for size and color. Big and red there in the next few weeks also probably means cockerel.