Trump was right to refuse to say if he'll accept election results if he loses, but ...

A key moment in Wednesday night's debate came near the end when moderator Chris Wallace challenged Donald Trump to say whether he will accept the results of this election.

The question became relevant over the course of the past week as Trump has made several statements that the election may be "rigged" against him. Considering the fact that it's never a good idea to agree to something before you know all the key facts, Trump's refusal to unconditionally say he'd accept the results was actually a good move. But he failed to give the best reply that could have turned this latest controversy in his favor.

Trump's verbatim final answer to the question was: "I will tell you at time, I'll keep you in suspense." In one key way, that was the best answer because it keeps his supporters pushing for a different result and it frees him from being unable to legally challenge the results if indeed some vote tallying questions do arise.

Don't be too shocked by the chances of that happening, unless you're too young to remember the weeks and weeks where the Al Gore campaign fought the Florida presidential vote results in 2000.

But Trump failed to say the few extra words that could have clarified that. The best response would have been to say that he won't answer that until he's sure nothing illegal has transpired and doesn't need to fight the results like Hillary Clinton and the rest of the Democrats did so vehemently against George W. Bush's campaign 16 years ago. By not doing that, the Clinton team and most of the news media will likely pounce on Trump for advancing divisive and dangerous conspiracy theories about the electoral process. Of course, they've been doing that already for the last few days anyway.

Trump is right that most of the media is indeed stacked against him and looking to twist his words. But he gave them plenty of rope to hang him with by not explaining why he can't be so foolish as to promise to concede before the election is even over. Simply by pointing to the Bush-Gore mess of 2000, he could have easily explained that position and possibly spiked the continued attacks on him for supposedly promoting divisive theories and charges. He didn't and it represented yet another missed opportunity for Trump in this campaign.

Commentary by Jake Novak, CNBC.com senior columnist. Follow him on Twitter @jakejakeny.

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