In an email exchange later, Castellanos explained that Jindal, who is putting all his chips on Iowa and trying to win that state’s most conservative voters, was targeting his message to that state while Christie, who is betting on doing well in more moderate New Hampshire, was pursuing an equally specific strategy.

“Having Christie in the undercard debate gave Jindal an opportunity to be the underdog against the big dog, polarize conservatives against moderates, and pit Iowa conservatives against New Hampshire independents,” Castellanos wrote. “Good for both men.”

After the debate, I asked Jindal whether he believes it is possible to be too aggressive in a debate, and if he worried his repeated challenges to Christie might turn off voters. The answer: No. “I think [voters] are tired of Republicans who go along to get along,” Jindal said. “Look, it’s easy to give platitudes. It’s easy to say hey, we all hate Hillary Clinton — not hate her personally, but we dislike her policies — but this election is about more than that.”

Jindal’s top strategist, Curt Anderson, argued that an angry electorate will see Jindal’s point. “Have you talked to primary voters this year?” Anderson asked in the post-debate spin room. “You can’t be as angry as these people are. You just can’t. Now, you can offend the delicate sensibilities of the DC press corps, of course, but in terms of being too aggressive on fighting for smaller government and the things we believe in, I don’t think that’s possible.”