said by Dunlop:Wouldn't it be 1 entry for the e-mail that is associated to you TSI account?
As Lothario said, they can't limit the contest or it could be interpreted as requiring purchase to participate which would make it a lottery and illegal. That said they have some weird language in their rules like:
A person entering must provide a valid email account associated with a domain that can be identified by a reverse domain name search as part of his/her contact information.
To me that language suggests that all .ca personal domains, webmail domains, etc are not valid for the purpose of the contest since they can't be reverse searched for the contact info. I'm sure that's not the case though.