A Republican running for governor in Michigan is playing up the Jan. 6 charges against him.

Ever since Ryan Kelley, a Republican candidate for governor in Michigan, was charged last month with trespassing and other crimes connected to the storming of the Capitol, he has openly embraced his status as a Jan. 6 defendant.

On Friday, Mr. Kelley again leaned on a part of his biography that many candidates might have run from: He put a post on his official Facebook page demanding that “all the J6 prisoners” be released from federal custody.

“Every American should be outraged,” wrote Mr. Kelley, who is not in custody as he awaits his trial. “Remember, you could be next for any reason ‘big government’ doesn’t approve of.”

In early June, when he was charged with four misdemeanors connected to the riot at the Capitol, Mr. Kelley became the first person running in a major state or federal election to be charged in the attack. Prosecutors say he used “his hands to support another rioter” who was pulling down a metal barricade outside the building, and that he gestured “to the crowd, consistently indicating” that it should continue moving toward an entrance.

With polls showing him lagging behind the front-runner, Tudor Dixon, a businesswoman and conservative commentator, and other candidates, Mr. Kelley, a real-estate broker, is unlikely to win the Republican primary on Aug. 2. The winner will face the incumbent, Gov. Gretchen Whitmer, a Democrat.

As recently as Wednesday night, during a candidate debate, Mr. Kelley spoke openly about his Capitol riot charges, treating them as an asset, not a liability.

He claimed, for example, that after his arrest, Airbnb shut down his account.

“Look how hard these people are trying to silence me,” he said. “They’re not trying to silence any of the rest of you.”