MILWAUKEE -- Four-term Milwaukee County Sheriff David Clarke has his first serious challenger in the upcoming election for his seat.

Current Major League Baseball Head of Security and former Milwaukee Police Department Captain Earnell Lucas will take on Clarke in the 2018 race for sheriff, TODAY'S TMJ4 has learned.

Lucas will be making his official announcement in the next few weeks, according to Sachin K. Chedda, with Nation Consulting.

The Marquette University graduate was born and raised in Milwaukee, and was captain for Milwaukee's Police District 3 before he left for Major League Baseball.

Though Sheriff Clarke's views often align with conservative ideologies, he historically has run as a Democrat. That's where Lucas plans to challenge him - in the fall 2018 Democratic primary.

Sheriff Clarke was first appointed to his seat in 2002. He won re-election later that year, and has since won re-election in 2006, 2010, and most recently in 2014.

Clarke has yet to officially declare his candidacy for a fifth term as sheriff. TODAY'S TMJ4 has reached out to his office for a statement.

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