A campaign finance watchdog group unleashed a brutal attack on Republican Senate candidate Bob Schaffer on Tuesday, charging the former congressman with defending sweatshop operators at the behest of lobbyist Jack Abramoff in an ad set to air on Denver television stations. Campaign Money Watch also called on Schaffer to provide evidence for repeated claims he caused a sweatshop to shut down after his junket to the U.S. protectorate in the South Pacific.