On "Special Report," Charles Krauthammer said that Hillary Clinton's email scandal and questions about her trustworthiness are directly related to her dropping poll numbers.

He said the cumulative effect of the email scandal, questions about the Clinton Foundation and doubts about her trustworthiness are catching up to her.

Krauthammer added that the rise of Bernie Sanders reveals how much the left-leaning portion of the Democratic base sees Clinton as too centrist.

He explained that the support for Sanders - and for Donald Trump and Ted Cruz on the Republican side - is indicative of a widespread anti-establishment, anti-Washington sentiment.

"I think it is an expression that, 'She's not the one we want,' at least among a large number."

Watch more from the "Special Report" panel above.

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