A former U.S. Capitol Police officer who bloodied his fists in hand-to-hand combat and endured pepper spray and racist vitriol defending the American seat of government against rioters on Jan. 6, 2021, is now seeking to return to the building as an elected representative.

Harry Dunn, 40, announced Friday morning that he is running for the Democratic nomination to replace Rep. John Sarbanes, D-Md., joining a growing field of candidates in what is expected to be a competitive primary.

Dunn, who served 15 years on the force and was one of four officers who testified before the House committee investigating the attack on the Capitol, said in an interview Thursday that he is entering the race because he believes democracy is at stake in this election. And, he said, he wants a seat at the table as leaders negotiate the country’s path through one of the most fractured and turbulent periods in its history.

“I’ve done all that I can do in my role as a Capitol Police officer,” said Dunn, who resigned from the force last month to run for Congress. “It’s no exaggeration to say that we are one election away from the extinction of democracy. And I believe that now, with this open seat in the district, it gives me an opportunity to continue to fight more for the country, the Constitution and the people of Maryland’s 3rd District.”

Dunn said he was frustrated that some congressional Republicans were misrepresenting the events of Jan. 6 and were not supportive of the Capitol Police or D.C. police officers who fought to protect them. Twenty-one House Republicans voted against awarding the Congressional Gold Medal to all police officers who responded on Jan. 6.

The frustration Dunn felt is part of what he said led him to consider running for Congress. As a police officer, he didn’t feel he was completely free to advocate for change or express his opinions on the events unfolding in the country - or to challenge the statements that some members of Congress were making.

“I was a little handcuffed with what I could do as a member of the Capitol Police because the people that we were responsible for protecting were also some of the people who were peddling the misinformation, the lies and whitewashing that we went through,” he said. “Not being able to protect them never came into question at all. But being able to effectively, morally look them in the eye when I know they are tearing down our democracy, it just didn’t sit right with me from the start.”

Dunn recounted many of his Jan. 6 experiences in his best-selling book released last year, “Standing My Ground: A Capitol Police Officer’s Fight for Accountability and Good Trouble After January 6th.” In the book he writes: “I speak out not because I want something for me but because I want accountability. I want the people responsible for that day, including Trump and anybody else who conspired to breach the Capitol and try to halt our democracy, to pay a price, just like we paid a price.”

A year ago, on the second anniversary of the Jan. 6 attack, President Biden awarded Dunn and 13 others the Presidential Citizens Medal for their efforts to protect the Capitol that day or to fairly carry out the 2020 election.

In addition to focusing on specific threats to democracy, Dunn said if elected he will concentrate on ensuring reproductive rights, pushing for “common-sense gun control” and protecting voting rights. He also wants to propel treatment of mental health issues to the forefront, saying he is passionate about getting rid of the stigma attached to expressing mental health concerns.

But if Dunn is to win the May 14 Democratic primary for Maryland’s 3rd District, which includes all of Howard County and sections of Anne Arundel and Carroll counties, he’ll have to beat a slew of contenders, including several with much more political experience. And he’ll have to begin raising money immediately, something he said he is looking forward to doing.

Two state senators, Sarah K. Elfreth and Clarence K. Lam, and three state delegates, Mark S. Chang, Terri L. Hill and Mike Rogers, have announced their candidacies. And there are two others - entrepreneur Abigail Diehl and Kristin Lyman Nabors, a research nurse - who, like Dunn, have not held elective office.

There are two candidates running in the Republican primary - Bernard Flowers and Jordan Mayo - but the seat is considered safely Democratic. Biden won 69 percent of the district’s vote in the 2020 contest against then-President Donald Trump.

The racially diverse district is 57 percent White, 18 percent Black, 11 percent Asian and 8 percent Hispanic, according to a Census Reporter analysis. It has a median household income of just under $120,000.

Dunn, who has a 12-year-old daughter, grew up in Prince George’s County and lives in Montgomery County. He said he will move to the 3rd District if he is elected.

Before joining the Capitol Police in 2008, Dunn had hoped to pursue a professional football career. He played football at James Madison University as an offensive lineman for all four years. He graduated in 2005 with a degree in health science.

Though Dunn has not shied from calling out elected officials who he believes have not been truthful about the events of Jan. 6 and have undermined democracy, he said he still thinks there is an opportunity for reconciliation among America’s warring parties. But, he said, it will only happen if Trump’s grip on GOP leaders is weakened.

“Once Donald Trump is out of the picture, I do believe there’s a way to get back to common sense and logic in the halls of Congress,” he said.