When John Oliver took the place of Jon Stewart’s hosting duties on the Daily Show it was unknown if the ratings would set sail or sink. Stewart has been on an eight week hiatus to direct a film - the very first in his hosting years of the Daily Show.
During the same time frame as last summer (in the middle of the 2012 election), The Daily Show's ratings only slipped slightly in Comedy Central's young male audience. The series held its .97 rating among both men 18-34 and adults 18-34. Although, the average viewership dropped 13 percent in Live+Same Day returns, while posting even smaller losses in adults 18-49.
During the 2012 election year in the months of July-September, during the Republican and Democrat National Conventions, Stewart and Colbert each gained 24 and 23 percent ratings boost.
The Daily Show still has the lead advantage as it maintains it’s strong young adult and male audiences; who rival with Jay Leno and Jimmy Kimmel.
As for Oliver as the Daily Show host, he definitely benefited from hosting the show, but his likeability was 50/50. Some say he didn’t perform as a host, while others say that the show was more than capable of performing without Stewart.