Trouble with Adbrite Code

Hey guys I am using blogger and am trying to insert the adbrite code to my site but I keep getting this message:
Your template could not be parsed as it is not well-formed. Please make sure all XML elements are closed properly.
XML error message: The reference to entity "br" must end with the ‘;’ delimiter.
I have no idea what this means or how to fix it. Any advice would be aweseome.

Original post by maxmitchell