Watch: Fox News' Tucker Carlson and Britt Hume debate possible Republican primary challenge to Trump

Donald Trump is holding a campaign-style rally in Nashville tonight, which got the boys at Fox News reminiscing about his wild rallies during the 2016 campaign.

Especially the early rallies—the ones from the primary. Which naturally led host Tucker Carlson and senior political analyst Britt Hume to the question of whether someone like Ohio governor John Kasich or Arizona senator Jeff Flake will primary the president and hope that with a narrow field they can somehow knock him out.

"It's kinda over—it's Trump's party now?" Carlson said, questioning.

They then debated how closely Trump holds to Republican orthodoxy, concluding that Trump has more or less rewritten the party platform.

"It would have to be on the issue of personal character," Hume said. "Whether that would work in a Republican primary at this stage—I don't think so."

"So on the issue you don't see any kind of challenge for the nomination?" Carlson asked.

Hume said he did see one thing that could change that: A trade war that damages the economy.

Watch below.