2016 presidential election vote among ... Voters in households without guns Voters in households with guns Hillary Clinton Donald Trump

Americans are deeply split along demographic lines, but there aren’t many demographic characteristics that embody America’s cultural divide better than gun ownership.

In the wake of the mass shooting in Las Vegas on Sunday, the polling firm SurveyMonkey published a pair of maps from its 2016 presidential election exit polls. It showed the electoral maps for voters who said they had a gun in their home, and for those who said they did not.

In every state but Vermont – perhaps the most liberal state in the country, but one where many, including Bernie Sanders, support gun rights – voters who reported living in a gun-owning household overwhelmingly backed Donald J. Trump.

The opposite is true for voters who said they did not live in a home with a gun. In all but one state that could be measured, voters overwhelmingly preferred Hillary Clinton. (The exception was West Virginia; not enough data existed for Wyoming.)

Over all, gun-owning households (roughly a third in America) backed Mr. Trump by 63 percent to 31 percent, while households without guns backed Mrs. Clinton, 65 percent to 30 percent, according to SurveyMonkey data.

No other demographic characteristic created such a consistent geographic split.

Comparable to the Racial Divide

American politics is deeply divided by race, and the gap between white and nonwhite voters is similar to the gap between households with guns and those without. But Mrs. Clinton won white voters, often by a wide margin, in 10 states and Washington, D.C., worth 139 electoral votes in all. And Mr. Trump may have been competitive among nonwhite voters in a few conservative states, like Oklahoma. (The poll data among nonwhite voters is sparse in several small states and subject to a considerable margin of sampling error.)

Nonwhite voters White voters

The split among white voters without a college degree and the rest of the country is also distinct. But Mr. Trump would have probably won without white working-class voters in several states, particularly in the Great Plains, according to the SurveyMonkey data.

Everyone but working-class whites Working-class whites

This is not to say that gun ownership is a bigger divide in American politics than race or the combination of race and education, or a bigger driver of America’s political divide. After all, part of the reason gun ownership splits voters so starkly is because gun owners are more likely than Americans generally to be white, less educated and living in a rural area. Over all, 83 percent of gun household voters were white in 2016, according to the SurveyMonkey data.

But it might not be merely demographics. Mr. Trump appeared to fare better in the SurveyMonkey data among gun-owning households than non-gun-owning households even after considering the voters’ race and education. He won white voters without a degree who lived in gun-owning households by 74 percent to 21 percent. He even won college-educated white voters in gun-owning households, 60-34, and fared better among nonwhite voters in gun households, losing, 61-34. Mrs. Clinton won nonwhite voters over all, 75-21.

Even so, education, race and religion tend to do a better job of predicting an individual’s presidential vote choice. It is probably fair to say that gun ownership embodies America’s partisan divide more than it drives it.

The Urban-Rural Divide

Urban voters Rural voters

For that same reason, density also comes close to approximating the divide between households with guns and those without. Not only does it correlate with gun ownership, but it also correlates with race and education.

Marriage

Unmarried voters Married voters

Marriage rates are also correlated to today’s political divide. Unmarried adults are likelier to be young and nonwhite, and concentrated in urban areas. But it’s not as strongly tied to a political issue. In this respect, gun ownership is unique among the demographic or household characteristics considered so far.

Other categories that blur the line between demographics and issue politics – like religion, union membership and military service – don’t yield such a pronounced split.

Religious divisions

Non-evangelical voters Evangelical voters

Atheist or nothing in particular Protestant or Catholic voters

Seldom or never attend church Attend church at least once a week

Religiosity – how often someone goes to church – has been a strong predictor of party affiliation, with frequent churchgoers much more likely to be be Republicans. The political preferences of more religious Americans yield a deeply red map, with religious voters from just three (relatively large) states – California, New York and Maryland – preferring Mrs. Clinton. Nonwhite voters most likely represent a disproportionate share of Democratic-leaning religious voters in many of these states.

On the flip side of this relationship are the religious “nones,” a large and growing group of voters who are atheist or do not identify with a religion. These voters tend to be younger than the overall electorate, one reason they strongly preferred Mrs. Clinton in 2016.

Union membership

Union member in household No union member in household