All you do is set up a URL channel with your blogger domain. I have one set up for all my blogger blogs. It takes just a couple of minutes.
It is quite easy. All you do is sign in to Adsense and go to the Adsense setup tab and click on channels. From there just click on URL channels and then add URL channel At that point you just put in the domain name like "domainname.blogspot.com" Adsense reports will start to show impressions, clicks and earning for that domain.
Awesome! I've been wondering the same thing. I don't know how I missed that option before. Thanks for pointing that out!