For me anyhow.

If you mean in general, I think drama is easier for most people. Horror can be very subjective: what is scary to me is not necessarily scary to you. Drama tends to cover things that are more universal.

^Agreed with Pith.

That, and drama is often based off of realism (e.g. situations that can actually happen to people) even though things are sometimes blown out of proportion to make the situation more dramatic. I personally find something easier to write if I can relate to the situation. Whereas horror tends to be, in many cases at least, fantasy-based. I've always been awful at writing horror stories (and believe me, I've tried). I can begin to build up suspense, but when it gets to the climax the whole thing just flops. If I don't believe something can happen, I find it very difficult to convince a reader that it's happening in my story. Maybe my horror stories would be better if I just didn't bother to finish them.

It's funny, but I generally find the drama genre to be scarier than the horror genre. Again, it may be because I can relate to it more. For example, a serial killer who can murder people with an effortless swipe of their weapon doesn't bother me much, but someone in hospital on a life support machine will make me a nervous wreck.