Democratic presidential candidate Joe Biden has been accused of plagiarizing a part of his acceptance speech at the Democratic National Convention.

Similar allegations arose during his failed 1988 campaign for the White House.

What are the details?

Several Canadians took to Twitter calling foul during the broadcast of Biden's speech Thursday night, accusing Biden of lifting the words of departed liberal Canadian politician Jack Layton, who passed away in 2011.

CBS News Washington correspondent Alexander Panetta noted, "A number of Canadians are struck by the similar parting words of Biden's speech to the final words of Jack Layton's farewell letter before his death."

The reporter provided a side-by-side of the excerpts.

In Biden's speech, he said, "For love is more powerful than hate. Hope is more powerful than fear. Light is more powerful than dark. This is our moment. This is our mission."

Layton's quote read, "My friends, love is better than anger. Hope is better than fear. Optimism is better than despair. So let us be loving, hopeful and optimistic. And we'll change the world."

Canadian media picked up on it, too. Left-leaning outlet HuffPost Canada declared, "Joe Biden's DNC speech sounded a lot like a Jack Layton quote," while conservative publication The Post Millennial noted that "left-wing Canadian activists" were making the plagiarism accusation. Both outlets compiled examples of tweets from users claiming Biden stole Layton's words.

HuffPost did not receive a response from the Biden campaign on "whether Layton was a reference for the speech," but the outlet noted:

Even Layton wasn't the first Canadian politician to mobilize 'love is better than hate' phrasing. That honour goes to prime minister Wilfrid Laurier, who said something similar in 1916.

'I shall remind you that already many problems rise before you: problems of race division, problems of creed difference, problems of economic con­flict, problems of national duty and national aspiration,' Laurier said during a speech in London, Ont.

'Let me tell you that for the solution of these problems you have a safe guide, an unfailing light if you remember that faith is better than doubt and love is better than hate.'

Accusations of plagiarism have dogged Biden in the past. Last year, Business Insider wrote an entire piece spelling out how "Joe Biden's first presidential run in 1988 cratered amid multiple instances of plagiarism."

The outlet pointed to two New York Times reports from 1987, exposing instances where Biden was accused of plagiarism. In one, "Biden acknowledged plagiarizing a law review journal for a paper during law school, and asked school administrators not to be expelled."

The second report from The Times was published within weeks of Biden dropping out of the race.

As Business Insider described:

During his failed 1988 run, Biden lifted portions of a speech by United Kingdom Labour MP and Margaret Thatcher challenger Neil Kinnock.

During an event at the Iowa State Fair, Biden mimicked entire portions of Kinnock's speech from earlier in the year. At one moment, Biden repeated the line that he was the first 'in a thousand generations' to graduate from college, gesturing to his wife in the exact same way Kinnock did, while also saying the same line about her education and lineage.

Biden would later acknowledge that he in fact did have relatives who attended college, directly contrasting the Kinnock lines.