Responding to a knock, Cheyenne Harris cracked open the front door of her Fort Davis Park home and peeked outside to find two people in bright green work vests.

“Hello, we’re with the Mayor’s Office on covid-19,” they said. “We’re wondering if you and your family have been vaccinated?”

They were part of the D.C. mayor’s Covid Community Ambassador program, a recent effort to hit the ground and talk with neighbors about the importance of being vaccinated. The ambassadors program is specifically targeting neighborhoods in Wards 7 and 8, which are majority Black and continue to lag behind the rest of the city in vaccinations.

On Saturday morning, before heading out, about 120 ambassadors — all in bright green T-shirts and vests — gathered in the Hillcrest Recreation Center. At the front of the room, Steve Walker, director of the mayor’s office of talent and appointment, instructed the crowd about their goals and plan for the day.

“Who’s ready to save lives today?” Walker said at the end of the session.

“We are!” The crowd responded with some light cheers.

Along with a number of vaccine incentives, the initiative is part of a push to increase D.C.’s vaccination rate as the city continues to reopen, loosen restrictions and welcome tourists back. It’s also designed to reach those facing obstacles, such as lack of transportation, that make it more difficult to access the vaccine.

According to data from the mayor’s office, about 62 percent of D.C. residents have received at least one shot of a vaccine. In Ward 7, about 29 percent of residents have been vaccinated, and only 23 percent of residents in Ward 8 have gotten a shot.

D.C. Mayor Muriel E. Bowser (D) has partnered with seven nonprofit organizations for each to hire 25 to 45 ambassadors to go knocking door to door to help people understand the importance and safety of the vaccines. The ambassador group is made up of people who also live in the community, in order to better connect with residents.

Standing outside of her home in Fort Davis Park, Harris, 33, answered that she had not been vaccinated. She was considering it but hadn’t yet made up her mind, calling the shot “iffy.”

“We want to make sure everybody is safe in your home,” Taniecia Byrd, one of the community ambassadors, told her.

Harris listened intently about the incentives available — like the $51 gift cards given to everyone vaccinated at Anacostia High School, Ron Brown High School and the R.I.S.E. Demonstration Center — and the transportation resources available to help her get to the vaccination site if needed. She filled out a form with her contact information for someone to follow up in a few days.

Walker said that with the team of roughly 160 ambassadors working throughout the day, he anticipated knocking on close to 8,000 doors in Ward 7 on Saturday. On their first Saturday two weeks ago, they knocked on 4,500 doors. The next Saturday, the number jumped up to 5,500.

Byrd, 35, and her knocking buddy James Clark, 58, used ­iPads to navigate from house to house to reach their targeted audience. They stood patiently for about a minute at each door before slipping handouts through the mail slot and moving on to the next house.

While a man in his 80s got out of his car, someone on the outreach team stopped him: “Have you been vaccinated, sir?”

“Oh, yes!” he said enthusiastically before heading inside.

Most of the doors Saturday morning were left unanswered. Occasionally, they’d be greeted by a barking dog or an automated voice from a security system. Many of those who did answer said they were already vaccinated.

“They ain’t! Go down there,” one woman said, pointing to her neighbors’ house.

Stuart Anderson, director of community engagement for the Anacostia Coordinating Council, one of the partner nonprofits, said he considers it a successful day if each of his outreach teams sends one person to get vaccinated. By noon, they had sent two.

As for Harris, she said she would still have to think about getting her vaccination before making a decision.

“I like the fact that they’re taking action,” Harris said. “I am considering it because it’s something we’re going to have to live with.”

And after the visit from the ambassadors, she said she’s leaning toward “yes.”