Clinton's latest earth-scorching attack video showcases Trump's white supremacist backers

In a truly damning tweet, Democratic presidential nominee Hillary Clinton published a campaign video profiling the spectrum of white supremacists who support her Republican opponent Donald Trump, from members of the Ku Klux Klan to backers of the so-called "alt-right."

Trump is courting and legitimizing white supremacists, the video argues. 

The voice of David Duke plays overtop an image of the former KKK grand wizard in a white robe and says, "Voting against Donald Trump, at this point, is really treason to your heritage."

The tweet instantly went viral, garnering nearly 2,500 retweets and 3,000 likes in under an hour.

"If Trump wins, they could be running the country," the end of the video warns in bold lettering. At the same time, audio of the Imperial Wizard for the KKK's Rebel Brigade Knights plays over, saying, "A lot of what he believes, we believe in."

Trump has refused to condemn white supremacists and the KKK in the past, and is himself grappling with a past rife with racially insensitive and xenophobic comments. 

In an interview with Mic in July, Thomas Robb, national director of the Knights of the KKK, talked about why he and his followers support Trump for president.

"Trump is espousing the ideals we've been promoting for years," Robb said. "They're talking about [these ideals] at the Republican National Convention. It makes our position credible."