This one’s a tough sell, because the teeth are different and it’s hard to find a picture of John with his mouth closed. Also their facial hair is often different, and the similarity is only really apparent when smirking or smiling.
But both John Oliver and Steve Carell have big noses, the same relaxed eyebrows, almost the same haircut, and somewhat similar contours. But they both have to be shaved, wearing glasses, and smirking or making a light smile. Too much smile and you can see John’s stereotypical English teeth.
I can see why one would make the comparison at a quick glance. The resemblance starts at about halfway down the nose. Taken as a whole,though, not really (to me).
If we were just sorting former Daily Show correspondents, I’d probably say Mo Rocca looks a little closer to John Oliver, just based on hair and eyebrows if nothing else.