Parsing Both Red and Blue in Late-Night TV Humor

They might be funny, but the late-night TV hosts are just as partisan in their jokes as the politicians they make fun of.

That’s the conclusion of a study by the nonpartisan Center for Media and Public Affairs at George Mason University, which calculated the percentage of jokes that comedians aimed at Democrats and at Republicans this year.

Jon Stewart, of Comedy Central’s “Daily Show,” and David Letterman of CBS’s “Late Show,” tend to single out Republicans and conservatives, while Jay Leno of “The Tonight Show” and Jimmy Fallon of “Late Night,” both on NBC, more often take aim at Democrats and liberals, the study found.

“Just as conservatives get their political news from Fox and liberals from MSNBC, conservatives are getting their political humor from NBC and liberals from Comedy Central,” said S. Robert Lichter, the media center’s president.

President Obama has been the biggest target for all four comedians, coming in for a combined 309 darts from Jan. 1 to Sept. 6. But Mr. Stewart, left, and Mr. Letterman aimed 58 percent of their jokes at the Republicans, while two-thirds of Mr. Leno’s subjects were Democrats. Mr. Fallon, right, made fun of liberals 78 percent of the time.

Among the sample jokes cited in the study: “The economy is so bad, Al Gore had to give himself a massage.” (Mr. Leno); “George W. Bush is writing a book …It’s all part of his war on literacy.” (Mr. Letterman); “Glenn Beck and his magic erasable truth board.” (Mr. Stewart).