As he steered his Straight Talk Express across the United States in recent weeks, Republican Sen. John McCain has tried to stay a-head of the immigration issue. But Friday the immigration issue delivered 36 or so heads to his Phoenix office — heads of lettuce, that is. McCain has been getting skewered in the media for comments earlier this month to a union group in Washington, D.C., that immigrants are taking jobs no one else wants, and offered them $50 an hour to pick lettuce in the Arizona sun for a summer, suggesting they couldn't do it. The senator didn't...