how to insert blank space between posts

Hey guys! It's me again with another problem. I'm quite happy with the theme so far, however there is one thing I can't do on my own.

I'd like the theme to insert blank spaces between posts, right now it looks like one giant and long post, because the date and title itself are not distinguished enough from the rest of the post.

(A picture is worth a thousand words)
http://i39.tinypic.com/o04iu8.jpg

I would like the space to be in different color than the post itself (white). Is it possible to do?

Thank you!