How is it that you were in receipt of this email and not Mr. Robinson?
What makes you believe he was? If you follow the link for the original post, you'll see it goes off site to http://a9.g.akamai.net/7/9/8082/v001/democratic1.download.akamai.com/8082/pdfs/20070510_freepletter.pdf.
Thus, he was referencing an off site pdf file of a letter sent by email to Free Republic.