2006 Hyundai Sonata starter/ electrical

2006 3.4 v6 sonata will sometimes not start. I will hold the key in start position sometimes up to 5 minutes and eventually car will suddenly start. This happens mostly in colder weather. Engine will not turn over, power everywhere in the car. Wires going to starter look fine. A relay under the hood will click while turning key back and forth to start when not starting also