Why won't any Republicans condemn the "Obama is a Muslim" myth?

Slate "Search for Christ on the White House Web site and the first item you'll find is the president's remarks at an Easter prayer breakfast. He didn't just welcome his "brothers and sisters in Christ," but also talked at length about why Christ's resurrection and the power of redemption meant so much to him. Previous presidents may have attended church, but Obama was doing something more. He was witnessing. Different churches may have different practices, but the ones I've attended don't usually greet such expressions of faith with scorn. The usual response is to say Amen."