Representative Katzenmoyer (D-Wisc.) is one of five Democrats who switched their votes to be against a gun control law. He did so because of a razor thin margin of victory in his district and fund raising problems. Josh Lyman threatened to endorse another candidate in the primary in person if Katzenmoyer didn't change his vote. After the meeting Katzenmoyer, O'Bannon and LeBrandt switched back to voting for the bill.
It is mentioned that Katzenmoyer comes from Eau Claire, Wisconsin, which would place him in Wisconsin's 3rd congressional district.