It is obvious that once you delete your blogger draft post without publishing it you can never recover it anymore, but read on as there is a solution when you read through this article, I was a victim of this, i wrote a blog post that took me several hours, but i did not publish the post yet due to the fact that the post was not yet complete, after i wrote the post to a point i stopped and logged out, cause there was some other thing that i wanted to do at that time, so i saved my draft post and planned to complete it and publish it the next time i log in, only to mistakenly delete the draft post that i spent a lot of time to write, can you imagine!
Don't also be a victim as i was learn from my mistake by reading this article that explains how to recover it >> http://www.allbloggersblog.com/2013/11/recover-your-blogger-draft-post-when.html