Election expert who correctly predicted Trump's election win gives 2020 update amid impeachment

Allan Lichtman, an American historian who has correctly predicted the last nine presidential elections, says the 2020 presidential contest is "very close and very difficult call."

"This is a very close and very difficult call. I don't think either the Democrats or the Republicans should be sending up any victory flags at this point. Too much is still up in the air and in the age of Trump, things can change very quickly," the American University professor told the New York Post in a recent interview.

Lichtman is best known for developing the "13 keys to the White House," the list of criteria he uses to derive his electoral predictions. The metrics include the economy, incumbency, military success and failure, scandal, third party candidates, and policy changes, among others. When five or fewer metrics are false for the incumbent, the system predicts an incumbent win; six or more indicates a challenger victory.

Though he said the 2020 election is "very close," Lichtman said the "inevitable impeachment" of President Donald Trump would only be his fourth false metric, meaning re-election is still in the president's corner.

"The party holding the White House would have to lose six keys to count them out. If you add in the inevitable impeachment, that would be a fourth key," Lichtman told the Post.

So what could push Trump over the metric threshold? Lichtman said a Senate trial and any subsequent fallout with voters.

For his part, Lichtman said he personally supports impeachment. He told the Post that American "democracy could go down in flames" if Trump is not "held accountable."

Over the summer, Lichtman predicted that Trump would cruise to re-election, saying at the time that there is only one roadblock to Trump's second term: impeachment.