“American Idol” was down 8 percent last night from last Wednesday in the overnight ratings. A 3.5 in the key demo was a marked departure from 3.8 last week. “Idol” still won the night. But the trend has been to win Wednesday and get steamrolled on Thursday. This is particularly vexing since “The Voice” returns on Monday–the only show on NBC that anyone watches. And now “The Voice” has planned at least one airing directly against “Idol” during sweeps on May 8th. It’s not like “Idol” doesn’t have good contestants. I am sold on Angela Miller. Her rendition of the Beatles’ “Yesterday” last night was sensational. But “Idol” has yet to light a fire with the TV audience. I still don’t know why Mariah Carey hasn’t sung “Almost Home” from “Oz the Great and Powerful.” We’ll see what happens tonight.