It’s March 4th. This day in 2004, Pat Toomey is challenging Republican Senator Arlen Specter in the Pennsylvania senate race — trying to outflank him from the right in the state’s primary. Jody, Niki, and Kellie look back at the moment where “to primary someone” became a political phenomenon, and talk to Nick Troiano of Unite America about why the primary system has been weaponized. Nick’s new book is “The Primary Solution” — it’s out now! Sign up for our newsletter! Get your hands on This Day merch! Find out more at thisdaypod.com This Day In Esoteric Political History is a proud member of Radiotopia from PRX. Your support helps foster independent, artist-owned podcasts and award-winning stories. If you want to support the show directly, you can do so on our website: ThisDayPod.com Get in touch if you have any ideas for future topics, or just want to say hello. Follow us on social @thisdaypod Our team: Jacob Feldman, Researcher/Producer; Brittani Brown, Producer; Khawla Nakua, Transcripts; music by Teen Daze and Blue Dot Sessions; Audrey Mardavich is our Executive Producer at Radiotopia Learn about your ad choices: dovetail.prx.org/ad-choices