Stewart’s role at HBO will be different from his post at Comedy Central. Instead of hosting a nightly, half-hour cable show, he’ll produce short online videos in which “Stewart will view current events through his unique prism,” according to HBO. We’ll have to see whether his audience follows him to a new platform. (Editor's note: They will.)
But according to smart people who study this sort of thing, Stewart wields measurable influence in presidential elections, though the beneficiaries might not be as obvious as you think.
A 2008 Pew Research Center study found that “Stewart’s humor targeted Republicans more than three times as often as Democrats” in a four-month sample, quantifying what had long seemed obvious to many viewers. A separate study of Stewart’s wisecracks during the 2004 party conventions, conducted by political scientists at East Carolina University, concluded that “the ridicule of Republicans focused much more on policy and character flaws. Humor pointed toward Democrats, on the other hand, tended to focus more on innocuous physical attributes.”
In other words, Stewart’s jokes about Republicans are not only more voluminous but also more pointed. None of this would matter if Stewart’s comedy had no impact on viewers’ opinions. But it does.
From the ECU study: “Analysis of panel data collected by the National Annenberg Election Survey during the 2004 national party conventions shows that exposure to The Daily Show’s convention coverage was associated with increased negativity toward President Bush and Vice President Dick Cheney. These relationships remain significant even when controlling for partisan identification and ideology. Attitudes toward the Democratic ticket, John Kerry and John Edwards, remained consistent.”
Of course, Bush went on to beat Kerry anyway, so it’s not as if Stewart has the power to pick the next president.
Then there’s this: The East Carolina researchers, Jody Baumgartner and Jonathan S. Morris, wrote in another scholarly article that during a primary, candidates with high name recognition are better positioned to withstand Stewart’s ribbing than their lesser-known rivals. Advantage, Donald Trump.
Baumgartner and Morris also concluded that Stewart tends to lower viewers’ trust in the political process, adding that “negative perceptions of candidates could have participation implications by keeping more youth from the polls.”
That may be the lone bright spot for Republicans in Stewart's return. Given that young voters overwhelmingly favored President Obama in the last presidential election, and were key in swing states, Stewart could theoretically aid the eventual GOP nominee — to whatever extent he suppresses the Millennial vote.