Here are the sponsors:anti-gun zealot Dianne Feinstein (D-CA) and Orrin Hatch (R-UT).
Sen Cornyn, John [TX] - 1/25/2005
Sen Grassley, Chuck [IA] - 1/25/2005
Sen Hatch, Orrin G. [UT] - 1/25/2005
Sen Kyl, Jon [AZ] - 1/25/2005
Sen Nelson, Bill [FL] - 6/6/2005
Sen Santorum, Rick [PA] - 6/15/2005
Sen Specter, Arlen [PA] - 6/15/2005
The only dem other than DiFi is Bill Nelson. I wrote Santorum and Specter about this when I got the alert, looks like I just reminded them to sign on if anything pigs
EDIT: I misread the summary status, DiFi is the main sponsor and is listed seperately.