Story highlights Gingrich: "I'd be a little bit cautious about automatically accepting that Hillary Clinton will be legitimately anything."

Gingrich added that the average American would agree there is widespread corruption in the government.

(CNN) Former House Speaker Newt Gingrich is defending Donald Trump's refusal at Wednesday's presidential debate to say he'd automatically accept the results of the election.

In a interview Thursday on the Mike Gallagher Show, Gingrich, a prominent adviser to the GOP nominee, cited anti-Trump Republicans, the FBI's investigation of Hillary Clinton's use of private email, and the release this week of an edited video suggesting a Democratic operative and staff hired people to incite violence at Trump rallies as evidence that the election might be rigged against Trump.

"So you look at all that stuff, and you say, I'd be a little bit cautious about automatically accepting that Hillary Clinton will be legitimately anything," Gingrich said. "We are in the worst cycle of corruption in American history, and in many ways, we resemble Venezuela and Argentina more than we resemble traditional America."

Trump in recent days has pointed the finger at the media and made claims that there is widespread voting fraud to argue that the election will be rigged if he loses. There is no evidence to support Trump's claim of an illegitimate election.

Trump's running mate, Indiana Gov. Mike Pence, appeared to break with Trump on Wednesday night before the debate, telling CNN that he and Trump will "certainly accept the outcome of this election."

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