Error, Lie, or Dog-whistle?

On the radio this morning, there was an interview with Ted Cruz about global warning. Unsurprisingly, he thinks that it's not real. He said many crazy things, all of them predictable. But then he said that if you want to know what's really going on, look at how the left talks about people who don't believe in global warming. He said that they call them deniers, which shows that this is a religious issue, they are calling people who don't believe their pseudo-science heretics.

Um? So, the only other place that I see denial used on a regular basis "Holocaust Denialist." Which, last I checked, wasn't a religious issue, but one of prejudice. Specifically anti-Semitism, but some large number of Holocaust deniers also get into some pretty weird nativist theories, but that's politics, not religion.

So, is Ted Cruz confused? Is he casually conflating religion with nativist "patriotism". Is he whistling about something? Is he just lying? I mean, I totally get how being a climate change denier works for his political campaign, and I get how trying to claim that it's a religious rather than a scientific issue plays into that political position, but what's he doing trying to conflate the terms "denier" and "heretic"?

Honestly, it seems vastly unsavory, but I'm not inclined to find much good in the man, so maybe I'm over-reacting.