Oil leak from camshaft sensor seal on passenger side valve cover

I have recently noticed a small oil leak on my garage floor. I thought maybe it was coming from the oil filter housing or oil cooler. 

This weekend I looked down in the engine valley where the oil cooler is located with a flashlight and there was no oil. I then noticed that the top of the valve cover on the passenger side was damp from oil right where there is a sensor. 

I researched the part and found that this is a camshaft position sensor. There is a round rubber seal that then sensor goes through.