Monday on MSNBC’s “Morning Joe,” host Joe Scarborough warned if Republican presidential front-runner Donald Trump doesn’t “clean up” the controversial endorsements he received from David Duke and the Klu Klux Klan, it could spell trouble for his campaign.

Trump had said he wasn’t aware of Duke in an interview with CNN’s Jake Tapper a day earlier, to which Scarborough called “disqualifying.”

“That’s disqualifying right there. It’s breathtaking, that’s disqualifying right there,” Scarborough said. “To say you don’t know about the Ku Klux Klan? You don’t know about David Duke?”

Scarborough expressed his confusion as to why Trump had been reluctant to reject the endorsement immediately.

“The most stunning thing, Willie Geist, is this isn’t buying him a single vote,” he continued. “I mean, is he really so stupid that he thinks southerners aren’t offended by the Ku Klux Klan and David Duke? Is he really so ignorant of southern voters that he thinks this is the way to their heart?”

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