Professor Allan Lichtman has correctly predicted every presidential election since 1984 and he thinks Donald Trump is headed for a win in November.

Lichtman, a distinguished professor of history at American University, says the forecast is not based on polls, demographics or personal political opinion.

In an interview with The Washington Post, he explained how he's using these keys, which he calls a "historically based prediction system," to forecast a Trump victory.

On Happening Now today, Jenna Lee discussed with Lichtman whether last night's debate or future debates can influence the prediction.

Lichtman emphasized that for the first time in more than 30 years, he's "hedging" his prediction because Trump - as he showed in last night's debate - could prove to be a "history-shattering candidate."

"[Trump] could change patterns that have held since 1860 in this country and enabled me to correctly predict every election since 1984," he explained.

The professor pointed out that Trump is the only candidate in decades who has refused to release his tax returns and appears to "lack the basic knowledge and temperament to be commander-in-chief."

"We have two competing historical forces. On one hand, this should be a change election. We should get a Republican president. But on the other hand, we have a candidate who could shatter patterns of history because of his unique status, which we saw on display last night."

Watch the full segment above.

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