Mr. Huckabee's spokesman, Hogan Gidley, said the former Arkansas governor will make an appearance after he participates in the so-called undercard debate, "to support our veterans." Mr. Trump's aides say the event is to raise money for wounded military veterans.

The move is basically a win-win for all involved. Mr. Huckabee will get more attention than he's been able to garner in months, and he will be affirming Mr. Trump's decision to skip the debate. What's more, it helps shift attention away from Senator Ted Cruz, Mr. Trump's main competitor in the race, and the candidate who is appealing to the evangelical voters that helped Mr. Huckabee win in 2008.

Mr. Gidley insisted there was no effort to harm Mr. Cruz or to take away from the prime-time debate.