I voted this morning in Washington, D.C. at a local protestant church, with a huge cross with the words “Jesus Saves” imprinted on it and quotes from the Bible posted everywhere.

What’s bothersome isn’t so much that Church and State are teaming up, though some have made that case (this year, the debate has been particularly fierce in Iowa, where one local church encouraged members of the congregation to vote after the service). My bigger concern is that the religious imagery and messaging might affect voter behavior, and determine the outcome of elections.

It’s not far-fetched. Recent research at Cornell suggests that something as seemingly insignificant as having a hand sanitizing dispenser in the room makes people express more conservative views; people also expressed more conservative views when researchers made the room smell bad. It sounds weird, but these are well-documented effects.

These subtle cues also play a role in the voting booth. A 2006 study [PDF] from Stanford University found that voters in Arizona were more likely to cast ballots in support of a state sales tax funding education if they voted in a school. In experiments, the researchers further found that voters were more likely to oppose stem-cell research if primed with religious images. These effects appear even if you control for demographics and political affiliation.

There is a simple explanation for these voting patterns: Voting behavior — like human behavior more generally — is often not rational, and is affected by our social environment in ways we don’t even realize. Part of the problem is that, especially when faced with a dauntingly long ballot like Californians are this year, voters save time and effort by relying on social cues and their ingrained assumptions about how the world works.

For instance, voters tend to assume reflexively that female candidates are less conservative than male ones, and also make assumptions about candidates based on race and occupation (if someone’s bio says they’re a small-business owner, that means they’re more conservative, right?). It’s part of an area of social psychology called “heuristics and biases,” and it looks at the ways in which our brains take shortcuts to reduce the cognitive load.

What it reveals about us is unsettling: Could the outcome of something as crucial as the 2000 presidential election, which came down to a handful of votes in Florida, have been determined by the number of people voting underneath some huge painting of the crucifixion?

Maybe — which is why I think we should all vote at home, online, and far away from a garbage can.