Retired Brig. Gen. Donald Bolduc announced Monday he will run for U.S. Senate against incumbent Jeanne Shaheen.

Bolduc (pronounced BALL-duck) a Republican from Stratham, served in the Army for 36 years and did 10 tours of duty in Afghanistan, according to a news release from his campaign.

The announcement came at the VFW in Concord.

Bolduc, 57, is the first Republican to declare a 2020 challenge to Shaheen, a Democrat who served three terms as governor from 1997 until 2003. After losing her first U.S. Senate bid to John E. Sununu in 2002, Shaheen unseated him in 2008 and was re-elected to another six-year term in 2014.

Speaking over the phone Monday evening, Bolduc said a “crisis of leadership” in Washington and encouragement from fellow Granite Staters led him to run for office for the first time.

“After I would speak, a Granite Stater or someone else would come up to me and say, ‘Hey listen, you should probably think about running for public office,’ ” Bolduc said. “I was humbled by those comments, but didn’t give it much thought. ... But the more people I talked to, the more I got a sense that I could bring leadership where leadership is needed in Washington, D.C.”

Bolduc said he’s frustrated with “politicians working for themselves” instead of their constituents.

On veterans issues, he said he believes a general lack of military experience among members of Congress is part of the problem, though he added that he does not believe non-veteran members are acting with any malice.

In a recent episode of “60 Minutes,” Bolduc was featured as an advocate for post traumatic stress disorder treatment — particularly for stellate ganglion block injections, which target a group of nerve cells in the neck that control “fight or flight” reflexes.

Bolduc says in the episode that he believes his career trajectory in the Army was limited because of how outspoken he was about his own PTSD.

Ahead of Monday’s announcement, Bolduc said he made a trip to the Monadnock Region to hear from voters.

“I was just in Dublin, and, you know, I have to tell you that the concerns there are affordable health care, affordable education, the addiction crisis, the mental-health crisis that we’re having,” Bolduc said. “They’re also concerned with immigration and border security, and keeping our economy strong under a free-market system.”

Heading into 2020, Bolduc said he hopes to run a grassroots campaign and meet as many voters as possible.

“I derive my energy from meeting people and understanding their concerns, and being able to formulate in my mind a process and ideas on how I can be of help to them and represent them as best I can.”

Jake Lahut can be reached at 352-1234, extension 1435, or Follow him on Twitter @JakeLahut.