Businessman and Republican presidential candidate Donald Trump continues to defend himself after his controversial comments about Fox News anchor Megyn Kelly. Here’s his explanation of what he meant when he said Kelly had “blood coming out of her wherever” during the GOP debate. August 10, 2015 (Alice Li / The Washington Post)

Many pundits predicted that Donald Trump’s attack on Fox News’s Megyn Kelly would bring him down as GOP frontrunner. As the old adage goes, you shouldn’t pick a fight with people who buy ink by the barrel, and in an era of partisan media, Republican presidential candidates shouldn’t pick fights with Fox News.

But as the post-GOP debate polls trickle in, The Donald remains in first place among the crowded Republican field. What gives? Why haven’t Fox News-watching Republicans turned on him?

The answer: The news media are not as powerful at shaping opinions as many media professionals think.

People are not sheep

In addition to Trump’s appalling comments about women, many predicted that his decision to attack Fox News would irreparably harm Trump’s standing among Republicans, most of who generally like and trust the network. Yet if decades of political communication research teach us anything, it is that the news media’s power over public opinion is far from guaranteed.

[New research shows just how much presidents try to manipulate public opinion]

People are actually quite adept at resisting persuasion, especially when they are wedded to an opinion. For instance, a substantial portion of the American public believes in widely dismissed conspiracy theories, such as that the 9/11 terrorists attacks were an inside job or that an alien spacecraft crashed in Roswell, N.M. It is very difficult to change these people’s minds.

Many conservatives tune into Fox News to see the news reported from their perspective, not simply to be told what to think. They will accept the messages that they hear on Fox as long as the network’s shows and personalities provide these viewers with reasons to support opinions that are consistent with their worldview, as shown, for instance, in Natalie Jomini Stroud’s research in “Niche News.”

Donald Trump has fans

If generals refight the last war, pundits reanalyze the last election. In the 2012 GOP primary, we saw a series of not-Romney candidates surge and collapse as the campaign progressed. But Trump isn’t the same as those candidates.

The parade of frontrunners in the 2012 GOP primary was about not-Romney voters discovering a potential alternative, scrutinizing the candidate, and then moving on when the candidate withered under the attention, as The Monkey Cage’s John Sides showed in his book “The Gamble.

But unlike those  2012 primary candidates, Donald Trump is a legitimate celebrity who is known beyond the realm of politics. Only 4 percent of respondents on a CBS News Poll conducted just before the GOP debate “hadn’t heard enough” of Trump to give an opinion. By contrast, 17 percent of respondents didn’t know enough about Newt Gingrich on a CBS News Poll conducted further along in the 2012 presidential election.

More important, most GOP voters like Trump. Although Trump’s favorability rating appears to have taken a hit after the debate according to a recent YouGov poll, he continues to have more admirers than detractors among Republicans. Despite his unwillingness to rule out a third-party candidacy and the fracas with Megyn Kelly, the same YouGov poll shows that he tied with Rubio as the debate’s winner. Those with a favorable view of him were more likely to disapprove of the Fox New moderators than those with a neutral or unfavorable view.

Apparently many of Trump’s supporters have chosen to side with him over Fox News. Perhaps Trump did not attract more fans, but he did not lose any either.

Does that mean Trump can win the nomination?

No. There is a big difference between being a celebrity with a fan base and a politician with a grassroots organization. Having a fan base is good for polling, but having a grassroots organization is necessary for winning elections.

[Trump wants to run his campaign outside the GOP establishment. Here’s why that hurts him.]

The GOP primary will not be decided on a single day or a national public opinion poll. It will be decided in a series of statewide caucuses and primaries. It takes a dedicated organization — not just a dedicated candidate — to ensure that people are registered to vote, informed about their polling place, and encouraged to spend part of an otherwise busy Tuesday casting a vote.

Given the lackluster quality of Trump’s political organization, it is doubtful that he will be able to convert his high poll standings into an election win.

Kevin Arceneaux is professor of political science and director of the Behavioral Foundations Lab at Temple University. He is co-author, with Martin Johnson, of Changing Minds or Changing Channels: Partisan News in an Age of Choice.