The latest Pew poll shows Barack Obama widening his slight lead among Catholics over John McCain since April from two to four percentage points, losing seven percentage points to McCain among Protestants, and increasing his margin over him among the unaffiliated by nine percentage points. The biggest shift came among white evangelicals, who now favor McCain over Obama 71-20, up from 65-32 a month ago. The current number represents the usual margin by which white evangelicals favor Republican presidential candidates over Democratic ones these days. So McCain’s evangelical problem, to the extent he has one, has only to do with motivating turnout. That could be a big issue, of course, but not as big as would be any evidence that Obama was picking up a significant new fraction of the white evangelical vote.