Documentary filmmaker and political commentator Michael Moore is "sorry to have to be the buzzkill here so early on," he said from the grounds of the Republican National Convention (RNC) on Thursday, but he thinks the GOP's presidential nominee Donald Trump "is going to win. I'm sorry."

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Speaking during an interview with HBO's Real Time with Bill Maher, 62-year-old Moore likened a Trump victory to the recent U.K. referendum to leave the European Union, stating, "I live in Michigan. Let me tell you, it's going to be the Brexit strategy."

In the wake of the surprise Brexit outcome, many voters admitted they had cast a "protest vote" in the belief that the U.K. would certainly stay in the E.U.

"I think one of the things I've been concerned about this week is...that we're sitting in our bubble having a good laugh at this shitshow, as you say, of a [Republican National Convention], but the truth is that this plays to a lot of people that he has to win to become the next president," Moore said.

"The population of schools has been wrecked, and the news media is just insipid and stupid and doesn't give the people the facts about what's going on," Moore said, adding that American voters are "easily manipulated."

Moore's prediction comes as RealClearPolitics' poll average shows that Trump is only a few points behind presumptive Democratic nominee Hillary Clinton. The latest Reuters/Ipsos poll, released Thursday, shows Clinton's national lead at just 4 points, down from 15 points in the same poll a week earlier.

"The total number of electoral votes in [Michigan, Wisconsin, Ohio, and Pennsylvania] in the rust belt, 64. All he has to do is win those four states. I was there during the primary, he went down and said they moved this factory down to Mexico, I'm putting a tariff on the cars, and it was music to peoples' ears," Moore said.

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