The plan is to remind voters that this will be a close election and every vote matters.
However, the debate is irrelevant. On the one hand, you have a liar who hates immigrants and wants to benefit wealthy Christians. On the other hand, you have a lousy debater who respects the rule of law and protects women's rights.
Nobody faced with this choice is going to ask, "Hmm, just how lousy at debating are we talking?"