Who has more album sales--Rihanna or Pat Benatar?

Pat Benatar was the most successful female album artist in history to that point, as far as putting together complete albums with great tracks as opposed to hits on an album combined with filler to get enough songs for the album, and then generating substantial album sales.  Rihanna has had a lot of today's hits, but which artist has sold more albums in their career?  (Answer after the break...)

Rihanna has sold 7.5 million career albums, Pat Benatar 11.5.