Wow. I watched about an hour of the "debate" last night but wasn't watching when he said that! His whole demeanor just screamed "dummy".
I usually don't watch those things because they really aren't "debates" per se. They are just platforms where self-centered idiots can do their virtue signaling and throw zingers at their opponents without ever really explaining or convincing anyone their own solutions are the best (it's a performance rather than a defense of ideas). That view was not changed last night.
That said, it appeared only one of the contestants was sporting any grey matter at all, even though I disagreed with virtually every one of their positions. I also think I got my fill of such stupidity in that one hour, so my debate watching days are over for this election season.