Maybe it has to do with how negative the media is with republicans but how positive they are of democrats.
I think it has to do with the fact that there are only a handful of unscripted and honest candidates on both sides, and the media portrays them as no-shots, fringers and fodder for the Clinton/Obama/Edwards/Giuliani/Romney/Thompson/Huckabee machine.
First Giuliani does not poll at 50%. Second, poll numbers = face time for message. Front runners, no message. The guys with a message are on the fringes, but no facetime to communicate it. That's why Paul is rising in the polls. He now has the money to counter the media blackout.
This news is good, but we will ultimately find out during the election. We will see if Americans will allow themselves to be brainwashed by the corporate media, or think outside the box and elect a man who actually follows Constitutional principles.