ramooch on "Keep params in url when navigate?"

Hi, i have this link that i use in an email marketing

http://plancero.net/citroen/?utm_source=BAODATA&utm_medium=email&utm_content=C3BERLINGO&utm_campaign=DARC

Got a form that tells me the medium that the visitor used to reach to the website, like email, facebook, twitter, etc.
The problem is that if the visitor leaves the page the parameters dissapear and i cant keep track of the medium

I want to keep

/?utm_source=BAODATA&utm_medium=email&utm_content=C3BERLINGO&utm_campaign=DARC

or at least the utm=medium

How can i do that?
Thanks in advance and sorry for my english