The largely unexpected rise in support for Republican and Democratic presidential candidates Donald Trump and Bernie Sanders — who represent two vastly different viewpoints — reflects how polarized Americans are on the political spectrum. The differences can be seen even within states where the political leanings of residents in one county can differ substantially from that of another.

Based on voting data compiled by political news organization Politico, 24/7 Wall St. measured the political leanings of county residents nationwide. The measures used to identify the most Republican-leaning county in each state include the percentage of county residents voting for Republican candidate Mitt Romney in 2012 and the county’s chosen representatives to the House and the Senate in the past five election cycles.

In a recent report from the policy think tank Pew Research Center, researchers found that Republican politicians tend to find their support among financially well-off voters, while the least financially secure Americans are considerably more likely to support Democrats.

Click here to see the most Republican county in every state.

Click here to see the most Democratic county in every state.

In general, people living in the reddest counties tend to be better-off financially compared to Democratic-leaning areas. In 32 states, residents of the most Republican-leaning county have a higher annual median household income than residents of the state’s bluest county.

While counties with strong Republican support tend to be wealthier, residents in these areas also tend to have lower educational attainment rates compared to the bluest counties. The percentage of adults who have attained at least a bachelor’s degree is lower than the comparable national rate of 29.3% in 39 of the 50 reddest counties. This is the case in just 26 of the bluest counties.

The racial composition of these counties can also help explain the Republican leanings of the area’s residents. The vast majority of residents in most of the reddest counties identify as white. In only three of the reddest counties a lower share of residents identify as white than the national share of 63% of Americans who identify as white. On the other hand, 28 of the bluest counties have smaller shares of white populations compared to the national average composition.

Voters in the reddest counties were almost always more likely than residents of other counties to vote Republican during the 2012 presidential election, and the share of votes cast for Romney were almost always a majority. However, in four of the reddest counties — Honolulu County, Hawaii; Plymouth County, Massachusetts; Washington County, Rhode Island; and Essex County, Vermont — a majority of residents voted to re-elect President Barack Obama in 2012. In these counties, Romney still captured the largest shares of votes compared to other counties in the state.

Some of the reddest counties are not as red as those in other states. Litchfield County, Connecticut, for example, has sent Democratic Rep. John Larson to Congress since 1999, yet gave 51.1% of its vote to Romney in 2012.

Click here to read our methodology.

These are the most Republican counties in every state.