Increase spacing between "recent posts"

Hi,

My blog is at http://onlinediamondbuyingguide.com/blog/ and I am running a twenty eleven child theme.

How do I increase the spacing on the “recent posts section” found on the right bar?

At the moment, it looks too cluttered because the vertical line by line gap is way too little.

– Recent post 1
– Recent post 2
– Recent post 3

I would like to change to spacing of about 8-10 pixels.

– Recent post 1

– Recent post 2

– Recent post 3

so that the gap is more obvious.

Thanks for any advice!

Paul