Well from what we have seen to date of Nighthawk, I would say that Daredevil, is more agile and faster reacting and would appear to be the superior hand to hand fighter.
Estimating Nighthawk's strength is difficult so to make matters easier, I will consider them to be similar in strength.
Nighthawk's costume provides some benefits to him, as it offers far more protection and will thus help insulate him from the full damage of daredevil's attacks.
Although Nighthawk does have several gadgets, some of them are limited in scope against Daredevil. For instance, Nighthawk's throwing daggers. Daredevil has been dodging ninja shuriken for a large number of years so this should be straightforward.
Daredevil also has his billy sticks (and the climbing line).
Overall, I would say that Daredevil should win based on the information known about Nighthawk at this time.
DD would take this. Even though Nighthawk is tougher, his skill has not been shown to be greater than DD or his agility. Basically, if he got a hold of DD there would be a problem, but the likelyhood is low. Nighthawk would be more on the level of the current Moon Knight.