Set Adsense clicks as a goal in Adwords

Is it possible to set Adsense clicks as a goal in Adwords? Alternatively, I'd like to track Adsense clicks as a goal in Analytics, but I would need to know the keyword that generated the click. I'm using the Display Network.

Does anyone know how this is done?

Probably, you'd have to implement some javascript though. What I'd do is maybe look into routing external traffic through a blank page on your site for a split second and that page contains the conversion tracking code. Make sense?