But even on its own, CNN.com consistently beats Foxnews.com by 7 million or 8 million unique users. Per comScore, the gap is even larger: 43.4 million uniques for CNN.com in June vs. 11.4 million for Foxnews.com. Plus, CNN.com regularly bests Foxnews.com in measures like page views, time spent and video streams—and it has opened an early lead in mobile (14 million uniques vs. 9 million in May for Fox, per Nielsen).

Those numbers have led some to wonder whether Fox’s lack of digital success could eventually undermine its influence in American news—particularly as a younger generation gravitates toward getting its headlines from iPhones and iPads rather than TV.

There are numerous theories as to why Fox lags so far behind online (executives declined to comment for this story). Longtime CNN.com producer Mitch Gelman, now vp of quality for Examiner.com, contends that it’s a simple question of quality. “CNN’s online service has been and continues to be better than Fox’s,” he said.

Fox was also late to a medium where habits are hard to break. “Six or seven years ago, Fox News was not as focused on the Web,” said Amy Mitchell, deputy director, Pew Research Center’s Project for Excellence in Journalism. In the early 2000s, said Mitchell, Foxnews.com was about promoting the net’s hosts. “That has changed.”