But the worst thing Hillary Clinton can do, it seems, is respond in kind. The Democratic nominee has enjoyed her highest polling numbers of late following the Democratic National Convention in Philadelphia, Pennsylvania over the summer. That was an event centered primarily on an attitude of positivity and hope—standing in stark contrast the Republican convention, mired in anger and fearmongering. Trump spent that week bickering with the parents of a fallen Muslim-American soldier, and his numbers plummeted.

Monday’s debate offers Clinton an opportunity to replicate her post-convention bump. The polls have it: When Clinton stays positive and Trump goes uber-negative, she comes out on top.

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