The best-selling author and retired army captain won the seat against contender Republican Dan Cox, flipping the mansion Democrat.
Both candidates were running to replace Republican Larry Hogan, who was term-limited.
Mr Hogan refused to support his party’s candidate bidding to take his seat, describing him as a “QAnon whack job” who was unfit for office.
Governor-elect Wes Moore was endorsed by Barack Obama, Joe Biden, and Oprah Winfrey.
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