Democrats have an ego problem, Teamsters president Sean O’Brien says.

The head of the nation’s largest union said the party that once stood for the working class has “somehow lost their way” and it just cost them the election.

He told the Herald Tuesday that the party of AOC — New York Rep. Alexandria Ocasio-Cortez — and VP Kamala Harris failed to grasp today’s political climate.

“They feel it’s a birthright that they would get our support,” he said. “It’s troubling. They can’t dictate how voters should think.

“It’s the fault of some Democrats who just forgot where they came from,” the Boston native added. “They need to be a little humble about it.”

The Herald reached out to O’Brien on Christmas Eve as his interview with Tucker Carlson was going viral. In that sitdown, O’Brien confirmed he was told by Harris pre-election that she wasn’t going to abide by the Teamsters’ full set of questions and answers.

That roundtable, held after President Biden announced he wasn’t going to seek reelection, was cut short with the VP only answering a quarter of their 16 questions. Trump answered all of them, the New York Post added.

“On the fourth question, one of her operatives or one of her staff slips a note in front of me — ‘This will be the last question.’ And it was 20 minutes earlier than the time it was going to end,” O’Brien told Carlson.

“And her declaration of the way out was, ‘I’m going to win with you or without you,’’ O’Brien added.

“Damn. I thought I was arrogant. That’s really arrogant,” Carlson responded.

The Post and Carlson’s podcast both state O’Brien called former Boston Mayor Marty Walsh, who had just left as Labor Secretary under Biden to take the job as head of the NHL players’ labor union, asking “Who does this (expletive) lady think she is?”

O’Brien told the Herald Tuesday he has not argument with anyone making money, it’s the “attitude” that galls him.

“The Democratic party, as I was brought up to believe in Boston, was always the party of the blue-collar, grassroots, working class who fought hard,” he said. “Let’s take care of them.”

As O’Brien told the Herald right after the November election, “there’s got to be a vision.”

The angst in the Democratic party after an election that swept President-elect Donald Trump back into the White House — and with Republicans set to control both chambers of Congress — is a stinging rebuke of the party of Joe Biden, Nancy Pelosi and Chuck Schumer, he added in mid-November.

“The Democrats need a reset. Nancy Pelosi needs to take a look in the mirror, and do it sooner than later,” O’Brien said. “Good leaders look for a succession plan and that clearly wasn’t the thought process.”

O’Brien, who first joined the Teamsters at 18 in Charlestown, said his Boston upbringing has him always seeking bipartisan solutions, but manipulation by entrenched media handlers and a Democratic party that had “no ground game” and stubbornly left “talent” on the sidelines, has exposed a critical “disconnect.”

He offered up the example of his powerful GOP convention address this summer that he was ready to deliver at the DNC — that’s until enemies on the “far left” ripped him for being seen with Republicans. The Teamsters voted not to endorse in this presidential election.

The International Brotherhood of Teamsters has over 1.4 million active members and 500,000 retirees making it one of the largest unions on Earth. O’Brien is the no-nonsense head of that guild and a lifelong Democrat. But the price of groceries doesn’t escape him, he added, or seeking out like-minded worthy leaders.

Vice President Kamala Harris. (AP Photo/Jacquelyn Martin)
Rep. Alexandria Ocasio-Cortez, D-N.Y., speaks during the Democratic National Convention in Chicago, Aug. 19. (AP Photo/Paul Sancya, File)