Map a domain to a subdomain with wordpress install

Hey Everyone, here is my question, I hope someone out there can help. First of all, godaddy is my hosting provider and domain registrar. So, what I am trying to do, is map one domain (mikemartin.me) to a subdomain of my other domain (me.mikemartinracing.com). I know its complicated, but it is what I want to do. WordPress is installed on the me.mikemartinracing.com domain. What I am essentially trying to do it set it up to use the mikemartin.me domain but the mikemartinracing.com hosting. I tried to do this with a hosted wordpress blog, but you have to pay to map domain (laaame). I had the domain mapped to my tumblr account for a while, so I know its possible, I’m just having trouble getting this working.