In Wyoming's Teton County, nearly 60% of residents are fully vaccinated -- almost double the statewide vaccination rate.
It's an effort that has been noticed in the state, which has one of the lowest vaccination rates in the country and where several counties have fewer than 30% of their population inoculated, state data shows.
"We have spoken to some of our other counties in Wyoming because they wanted to know what we were doing," Rachael Wheeler, the public health response coordinator at the Teton County Health Department, told ABC News.
As the highly transmissible delta variant quickly spreads throughout the United States -- now making up over 80% of new cases -- regions with high vaccination rates are expected to fare better, medical experts say.
ABC News spoke to Wheeler and officials in two other counties leading their states in COVID-19 vaccinations about their campaigns, what they've done and where they go from here.
McKinley County, New Mexico
McKinley County, which includes part of the Navajo Nation reservation, was one of the hardest-hit regions in New Mexico early in the pandemic.
For Adam Berry, emergency manager for the county, that may have helped drive vaccinations to where, as of Monday, over 94% of residents ages 18 and up have received at least one dose, according to the latest state health department data. Statewide, that number is 72.2%.
"The spring of 2020 was our first wave; we had a pretty good surge," Berry said. "We had the highest case number in the state, especially per capita, for several weeks and months, before things tapered off late summer."
There was a longer, second surge in the winter that filled Gallup hospitals and mortuaries to capacity, he said.
"There's very few people in the county that don't know at least one person that was sick, if they weren't sick themselves," he said. "Many people know one or more people that unfortunately died due to COVID-19. So I think it's very personal for a lot of people."
Berry said there was a little hesitancy in the beginning, but that "it didn't take very long at all for a lot of people to start lining up to get the vaccine." Being able to protect themselves and their family, as well as safely see people they had not seen in a while, were big motivators, he said.
The vaccination effort has involved coordination among the county's emergency management and public health offices, state health department, health care providers, community partners and federal agencies, including the Indian Health Service.
"It was definitely a big community effort. Everybody does their part to try to get as many people vaccinated as possible," said Berry, a volunteer paramedic who also helped administer vaccines when clinics were short-staffed.
One thing that worked to the county's advantage in administering the vaccine is having a significant percentage of the county served by the Indian Health Service, he said. Nearly 80% of the county's residents are Native American, according to the U.S. Census.
"A lot of other counties in New Mexico are dependent on local health care systems and private physicians to vaccinate the bulk of their populations," he said. "We were fortunate in that aspect that we have a large presence of Indian Health Service facilities to help take care of that population, which allowed for vaccines to come in directly from the federal government to that site."
The Indian Health Service held drive-thru events at the Fire Rock Casino in Church Rock and did outreach to the Navajo Nation "to make it more convenient" to get the vaccine, Berry said.
The county has lately been focused on bringing people back for their second dose if needed, as well as vaccination efforts in those ages 12 to 16.
Since May 24, the county has reported only three COVID-19 deaths, and the seven-day average of new cases is three, down from a peak of 109 in mid-November, state data shows.
There's still a lot of mask-wearing, though life has started to "look a little more normal," Berry said. "We've come a long way in the last year."
Lamoille County, Vermont
There's stiff competition to be the top county for vaccinations in Vermont, which has the highest vaccination rate in the country.
At the moment, Lamoille County holds that distinction, with over 85% of residents ages 12 and up having received at least one dose, according to state data.
"When we saw those numbers we were very happy about it," Aaron French, director of the Morrisville Office of Local Health in Lamoille County, told ABC News. "Every county's working really hard."