The data show numerous ways in which Fox News-watching Republicans have radically different beliefs from non-Republicans and even Republicans who do not watch Fox News.

Republicans who don’t watch Fox News, for example, are over twice as likely to believe climate change is man-made, compared to just 12 percent of Republicans who watch Fox News. According to the poll, 78 percent of Republicans who watch Fox News believe Trump has accomplished more than any other president in history, compared to 49 percent of Republicans who do not watch Fox News. And 79 percent of Republican Fox News viewers said they believed people within the FBI and US intelligence agencies were trying to sabotage Trump, compared to 49 percent of non-Fox News viewing Republicans and just 8 percent of non-Fox News viewing registered voters who did not identify as Republican.

“Where Republican partisan affiliation and the Fox News echo-chamber overlap, there is near unanimity on the politics and even the facts defining the Trump presidency. This is the ‘FoxHole,’” the pollsters said. “What the Navigator data demonstrates is this particular segment of the public is so vastly different from the rest, it may serve progressives best to focus their attention on everyone else.”