Howard Dean, a Hillary Clinton supporter, offered a theory Monday night about Donald Trump’s habit of sniffing during the presidential debate.

Cocaine may have been the culprit, the former Vermont governor and failed presidential candidate suggested on Twitter.

“Notice Trump sniffing all the time. Coke user?” he wrote.

The social media site erupted during the debate with similar speculation, but Dean was by far the most prominent Clinton supporter to ask the question. (RELATED: People Can’t Stop Talking About Donald Trump’s Sniffing On Twitter)

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