Madonna Johnson remembers driving through mostly farmland from West Des Moines to Waukee to drop her daughter off at dance class. That was 20 years ago.
Today, the former two-lane Hickman Road is four lanes and surrounded by housing developments, strip malls and big box stores.
“It’s very, very different,” Johnson said. “That’s a short time period for this amount of development to go up.”
Johnson, who grew up in nearby Warren County, moved to West Des Moines in Dallas County to raise her family a few decades ago. She currently chairs the Dallas County Republicans and lives in Waukee, where she says new housing developments and businesses continue to spring up on land once home to sprawling cornfields.
“Dallas County used to be really rural farming, so it’s always been a red county, but now we have builders slapping up houses and people moving here and moving into Iowa, not just from Polk County,” Johnson said. “That’s really where the rubber hits the road.”
Dallas County, IA
Over the last decade, Dallas County, on the western edge of the Des Moines metro area, has seen the largest population growth of all of Iowa’s 99 counties and is one of the fastest-growing counties in the country.
Since 2010, the county has seen a nearly 73% population increase, going from 66,751 residents in 2010 to 115,343 residents in 2024. Iowa’s total population growth was about 5% in the same time period. The county went from being ranked the seventh fastest growing county in the country in 2010 to the fourth fastest growing following the 2020 census.
Once a primarily rural area, Dallas County has both small towns, including Adel, Perry and Dallas Center, and suburbs where the county line slices through Urbandale, West Des Moines and Clive.
And with the significant population shift in Dallas County also came a political one. =
Dallas County population 2010-2024
Dallas County’s population nearly doubled between 2010 and 2024
Former Republican Sen. Mitt Romney won the county by 11.55 percentage points in 2012. President Donald Trump took the county in the last three elections by 9.43 percentage points in 2016, 1.97 percentage points in 2020 and 4.69 percentage points in 2024, his margins have remained steady compared to other counties in the state where he has significantly increased them year after year.
Similarly, the county has also swung leftward in gubernatorial races.
In 2014, the county went to former Republican Gov. Terry Branstad by 33.3 percentage points and in 2022, it went to Gov. Kim Reynolds by 8.1 percentage points.
Dallas County, Iowa: Presidential election voting trends
Since 2016, Democratic votes in the county have steadily increased
“You won’t see a lot of Republicans in Dallas County switching to Democrats. That’s not why we’re doing that now. It’s because of people moving into the area,” Roszak said. “That’s a lot of apartments, people coming in from the colleges, going into their apartments, starting their jobs.”
Industry in the county has boomed alongside the population. It’s home to a Wells Fargo campus and Sammons Financial. Last year, Apple opened a data center in Waukee and Microsoft has one slated to go up in Van Meter.
The county has the highest medium household income in the state, sitting at $102,349 compared to Iowa’s $71,433 average.
And as the state ages, Dallas County’s average age of 35.9 is below the state’s average of 39.1.