Former Capitol Police officer Harry Dunn on Friday announced his campaign for an open U.S. House seat in Maryland.

Why it matters: Dunn, whose announcement comes on the eve of the third anniversary of the deadly Capitol attack, gave gripping 2021 testimony to the Jan. 6 committee about fighting off rioters.

• The 15-year Capitol Police veteran has since authored a book about his experiences in law enforcement and received a Presidential Citizens Medal for his service.

Driving the news: Dunn told Axios in an interview that while the Jan. 6 attack was the "springboard" for the idea of running for Congress, "everything that's happened afterwards, the continued downplaying, the whitewashing, minimizing ... has kind of fueled me even more."

• Newly elected Speaker Mike Johnson's (R-La.) lead role in whipping up congressional support for a lawsuit aimed at overturning the 2020 election is "another motivation," Dunn said.
• In addition to abortion rights, voting rights and gun reform, along with the democracy-related issues for which he is best known, Dunn plans to campaign on health care and infrastructure.

The backdrop: In his testimony to the Jan. 6 committee, Dunn said he was called racial slurs by rioters, telling the panel it is "so disheartening and disappointing that we live in a country with people ... that attack you because of the color of your skin, just to hurt you."

• Dunn also opened up about the trauma he has faced in the aftermath of the attack, stating, "Jan. 6 still isn't over for me."
• Mental health, he told Axios, is another issue he is "pounding the pavement about,” saying he hopes to “break the stigma.”

State of play: Dunn faces more than a dozen Democratic primary opponents, including three state senators and two state delegates vying to represent a district that went for President Biden by 40 percentage points in 2020.

• "They may be well-established politicians, I'm a well-established public servant," Dunn said.
• Dunn added that he doesn’t “necsee them as people I'm running against. I just want to continue to tell my story.”

Background: Dunn is also a resident of Montgomery County, a suburb of D.C. located in Rep. Jamie Raskin's (D-Md.) district. Dunn told Axios he has lived in the state of Maryland his "entire life."

• "Now that I have resigned from the Capitol Police, I look forward to moving into the district once the people choose me to represent them," he said.

What they’re saying: Several former Jan. 6 committee members stopped short of endorsing Dunn but offered him praise and expressed enthusiasm about his run.

• “Go get em! Good man who put his life on the line for people who can't stand him, so he will defend everyone in his district in D.C.,” said former Rep. Adam Kinzinger, a Republican, who said he isn’t officially endorsing but is "certainly open to it and excited for his effort."
• Raskin said he's "not getting involved in the primaries” but “obviously I wish him well, I wish all the candidates well.”
• “I'm glad we've got so much energy in the Democratic grassroots,” Raskin added.

Between the lines: Of the timing of his announcement, Dunn said, "Jan. 6 is one of the days that put this whole thing in motion."

• "It was one where [democracy] was directly threatened, and I, personally, along with my coworkers, physically defended the Constitution, defended the members of Congress, defended our democracy," he said.
• "I think it was only proper to use this day as a reminder to individuals, because we can never forget Jan. 6."

Go deeper: Capitol Police officer who testified to Jan. 6 panel eyes House bid

Editor's note: This story has been updated to include comments from Jan. 6 committee members.