DENVER— America’s suburbs are today’s great political battleground, long seen as an independent pivot between the country’s liberal cities and conservative small towns and rural expanse.

But it’s not that simple. It turns out that these places in-between may be the most politically polarized of all — and when figuring out the partisan leanings of people living in the suburbs, where they came from makes a difference.

Fewer suburbanites describe themselves as politically independent than do residents of the nation’s urban and rural areas, according to a survey released Tuesday by the University of Chicago Harris School for Public Policy and The Associated Press-NORC Center for Public Affairs Research. The poll also found that the partisan leanings of suburban residents are closely linked to whether they have previously lived in a city.

“In the last decade, particularly in the past five years, I’ve felt a shift in having some liberal neighbors,” said Nancy Wieman, 63, a registered Republican and staunch conservative who has lived in suburban Jefferson County outside of Denver her entire life. “The ones who are markedly liberal have moved from Denver or other cities.”

Suburbanites who previously lived in a city are about as likely as city-dwellers to call themselves Democrats, the survey found. Similarly, Americans living in suburbs who have never resided in an urban area are about as likely as rural residents to say they are Republican.

Just 15 percent of suburban Americans say they are independent and do not lean toward a party, compared with 25 percent of urban Americans and 30 percent of rural Americans who call themselves politically independent.

That divide extends to the White House: 72 percent of ex-urban suburbanites disapprove of President Donald Trump’s performance in office, as do 77 percent of city residents. That compares with the 57 percent of suburbanites who have not previously lived in a city and 54 percent of rural Americans who say they disapprove of the president.