This is the Oil Pressure sending unit. Typically it can leak if not properly tightened, but there is no gasket. The cam position sensor is higher up and further right, but often the rubber ring sealing it can leak and drip down to the Oil Pressure. Also, valve cover gaskets could cause a leak in the similiar area. I suggest you make sure that the sensor is properly tightened, then check the other two possibiliites.