Elections

Here are the best moments of Clinton, Trump's fiery debate

This critical first debate comes as national and swing state polling has tightened. A recent national Quinnipiac poll showed Clinton up by 1 point in a four-way race including the Libertarian Party's Gary Johnson and Green Party's Jill Stein, while a Bloomberg poll showed a 2-point advantage for Trump. Clinton's average lead in recent four-way polls sits at 1.6 points and was as narrow as 0.7 points a week ago, according to RealClearPolitics.

Recent polls also show Trump taking a lead in swing states Ohio and Florida while gaining ground in Colorado.

Trump's ability to describe his often inconsistent policy stances and stay away from the insults and bluster that have defined his campaign will be under scrutiny. Democrat Clinton, on the other hand, will try to stay on message while facing the unpredictability posed by her Republican opponent.

The campaigns have taken different approaches to debate preparation, as Clinton has dedicated time to studying while Trump has left only small windows to prepare.

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