Nancy Grace and HLN enjoy best all-time ratings thanks to Casey Anthony

One-woman rage-factory Nancy Grace may not have won much favor among media critics for her ferocious coverage of the Casey Anthony murder trial. But her high-octane approach to the Anthony case has helped the oft-overlooked HLN win record ratings.

The latest numbers just came in via Nielsen: HLN's audience dominated cable news when the verdict was read during the 2:15 p.m. quarter-hour Tuesday, beating Fox News, MSNBC and its own parent network, CNN, each by a wide margin.

More than 5.2 million viewers tuned in to HLN when the jury found Anthony not guilty of killing her 2-year-old daughter Caylee in 2008, giving HLN, between 2 and 3 p.m., its best ratings ever for a single hour. Roughly 2.9 million were watching Fox News during the long-running trial's apex, 2.3 million CNN and 920,000 MSNBC.

HLN honchos don't seem to be sweating over how to keep the momentum going as Anthony fades from the headlines.

"I don't worry that this was our moment and now it's gone," one network executive told the Hollywood Reporter. "I think we have lots of stories to tell."