This year’s presidential election is one for the history books.

It contains every aspect of a traditional conflict and more: it’s adversarial, there’s zealousness, name-calling, and allegations that the process is “rigged.”

The three presidential debates leading up to the November 8 general election between Democratic nominee Hillary Clinton and Republican Donald Trump were each memorable for different reasons.

Boston College History Professor Heather Cox Richardson, author of five books including, To Make Men Free: A History of the Republican Party,says the final debate on October 19, was unprecedented for one reason.

The most quoted moment from that debate was when Trump refused to say if he would accept the results of the election.  Richardson says, “that was THE moment of the debate for sure.”

On the flip side, while Trump has consistently and publicly said the election is rigged, according to Richardson, other politicians in history have said this before.  She points to 1860 when the democrats refused to accept Abraham Lincoln as president. She says, “they didn’t challenge the election itself, but challenged being part of a country that would elect someone like Lincoln as president.”

In the 1890s, Richardson says, it was a commonplace for Republicans to complain that "elections couldn’t be trusted because they had been corrupted by immigrants or workers…people who were not legitimate voters.”

As a result, Richardson points out that violent political eruptions were  not unusual: riots, lynching’s, and posse’s that overturned established governments on the frontier.

What we can infer from the past presidential campaigns and the present moment, Richardson says, is that past presidential candidates made these accusations about unfair election rules when the margin of error between the candidates was razor thin. It was an attempt by a candidate to gain a lead over their opponent.

Richardson says in Trump’s case, the accusation of a rigged election is not helping to boost his campaign poll numbers and may, in the long run, be undercutting his campaign with undecided voters.

Richardson tells WGBH Morning Edition host Bob Seay that some aspects of the Trump campaign parallel Republican Senator Barry Goldwater 1964 candidacy, especially when it comes to temperament. Goldwater lost the race in a landslide to Democratic incumbent Lyndon Johnson. Goldwater captured only Arizona and five deep southern states.

Richardson says both men were prone to outbursts, but unlike Goldwater, Trump is more of a loose cannon.

Overall, Richardson says that she thinks the division within the GOP could be a good thing. After the election, the party will have a chance to realign itself. If the party can loose some extremists, it would have a chance to rejuvenate itself and become more of a progressive party, as it did under Lincoln.

To Listen to then entire interview with BC History Professor Cox  Richardson and Bob Seay click on the audio file above.