My Hubby never signed up for his mailing list. The poster on the lefty site didn’t either. Curious isn’t it.
You are probably on several mailing lists that Romney bought and consolidated and has resold. I get mountains of email from GOP candidates and causes that I never signed up for - some I never heard of before. They got that email address [which is a throwaway for just this purpose] from a newsletter signup or a candidate donation list which was resold.