Texture-based mouseclick detection

Hi all,
I’m making a little game where you have to click on moving objects to destroy them.

I also have a crosshair texture (attached to an empty gameobject) following my mouse movement.

Right now I handle click detection by implementing an OnMouseDown handler in my moving gameobject. The problem with this, however, is that when I click just on the edge of an object, the click misses, while the object was actually inside boundaries of the crosshair.

Is there any way I can detect if the texture overlaps a gameObject?

Do you have a collider on the object?

And can you post your script?