Dunham has been called "America's favorite comedian" by Slate.com, and according to the concert industry publication "Pollstar", he is the top-grossing standup act in North America, and is among the most successful acts in Europe as well. As of March 2009, he has sold over four million DVDs, an additional $7 million in merchandise sales, and received more than 350 million hits on YouTube (his introduction of Achmed the Dead Terrorist in "Spark of Insanity" is the ninth most watched YouTube video). "A Very Special Christmas Special" was the most-watched telecast in Comedy Central history, with its DVD going quadruple platinum (selling over 400,000) in its first two weeks. "Forbes.com" ranked Dunham as the third highest-paid comedian in the United States behind Jerry Seinfeld and Chris Rock, and reported that he was one of the highest-earning comics from June 2008 to June 2009, earning approximately $30 million during that period.