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Tonight on On the Record, Brit Hume spoke to UVA Center for Politics Director Larry Sabato about polls showing the 2016 race tightening.

Sabato said there are two factors in play. First, Hillary Clinton had a rough week, with her "basket of deplorables" gaffe and then her "lie of omission" over contracting pneumonia.

But he said the other point that needs to be made is that polls have switched from "registered" to "likely" voters - "and when you go to likely voters, you flush a lot of people out."

"Does anybody doubt which of these two candidates has the most enthusiastic followers? We all know the answer -- it's Donald Trump."

What this means, Sabato said, is that Clinton and Democrats have gotten a "warning...that they're going to have to do a heck of a lot more to stir their base and get them out to vote."

Watch more analysis above.

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