One of the big stories trending in the wake of the surprising Trump victory on Election Day is the significance of the stealth vote. Termed “undercover Trump voters,”  this block of people includes many who were unwilling to reveal their support for Donald Trump during the campaign in order to save both face and friends, and flew under the radar all the way to the ballot box.
It is believed that voters like this, reluctant to publicly air their views and intentions, were largely responsible for the Brexit vote in the UK this year—leading Trump to predict what is described as “Brexit plus plus plus”—a process of turning “voter disaffection into electoral triumph.”
So who are these stealth voters? Trump campaign manager Kellyanne Conway says they include traditionally Democratic groups such as union members, Hispanic voters, and women. And their existence, although impossible to prove, was suspected far in advance of Election Day.
Throughout the general election, Hillary Clinton led Donald Trump in the polls. In some states, she led by a significant margin. Some Hillary supporters predicted a landslide victory—to such an extent that Democratic leaders were encouraging supporters who were already confident about a Clinton victory, to make sure to get out and vote instead of relying on what the polls indicated would be a done deal.
Yet despite the polls showing Clinton in the lead, by the end of August, Conway and others were predicting that undercover voters could significantly impact the election. These were people who intended to vote for Trump but also wanted to maintain their friendships and relationships by claiming to be anti-Trump in order to remain socially desirable. Some correctly predicted that so called “hidden Trump voters” would take their concealed beliefs all the way to the ballot box. And they were right.
Many Americans are now scratching their heads wondering—how did this happen? In a country where citizens value freedom of speech and maintaining a diverse marketplace of ideas, how could so many voters have been afraid to speak up?
Casting a Secret Ballot: The Significance of the Stealth Vote
As I documented in an earlier column, "Admit it, You're Secretly Voting for Donald Trump, Right?"  it came to the attention of political analysts that Trump seemed to be polling higher in online polls as opposed to those conducted over the phone—where voters engage in live interaction with the questioner.  Even at that time, it was believed that the discrepancy was driven by voter concern over social desirability.
Given the unanticipated Trump victory, it appears that even exit polls did not capture the true sentiment of the electorate at large. Exit polls involve collecting data through approaching and interviewing people at a polling place after they have cast their vote. In addition, given the popularity of early voting, modern exit pollsters also call people who have already voted to inquire about their choice. 
The reality is that polling is only as reliable as voter transparency—and willingness to be interviewed. Because this method of data collection involves interaction with a pollster, many voters declined to interact, and among those who did, some were apparently less than forthcoming about how they voted, perhaps in order to save face or avoid anticipated controversy, even over the phone.
Trump Supporters and Political Engagement: Demographics Matter
In today's world, many people wear their political views on their virtual sleeve, expressing their views online. Others proudly display partisan passion through stickers on their cars and signs in their front lawns. The willingness to broadcast partisan passion, however, depends on demographics.
Some voters report that their willingness to display Trump lawn signs or bumper stickers depends on where they live and work, having encountered arguments, theft, and even vandalism as a result of showcasing partisan support in the “wrong” neighborhood. 
Others have observed that many rural neighborhoods were awash with Trump yard signs and bumper stickers.  This is consistent with research showing that voters are more likely to engage in political activity when surrounded by like-minded friends and family. 
On the other hand, the theory of social accountability reduces the likelihood of engaging in public political discussion for people holding opinions in conflict with community norms, or that would create interpersonal conflict. 
Unpopular Views and Political Disengagement—Not This Time
Stealth voters flew under the radar because they did not outwardly engage in political activity. This reality has been empirically corroborated. For example, one study showed that people were less likely to donate money to a candidate when their donations would be publically available on the Internet.  This was particularly true for those surrounded by individuals who shared different political views. 
On the other hand, the stealth vote arguably contradicted research showing that according to theories of social influence, people holding unique political views (i.e., Trump supporters within anti-Trump social circles) are more likely to withdraw from politics altogether in order to avoid the social costs of being exposed.  One study focusing on the impact of neighborhood on voting behavior found that Republicans living within “enemy territory” were less likely to vote. 
Research reveals that individuals with partisan preferences are more likely to vote when they are part of a like-minded community, compared with a community that is politically heterogeneous.  This is because within politically homogeneous areas, individuals enjoy the positive reinforcement they receive from friends and neighbors who hold the same political views that they do. 
Yet in this election, stealth voters did vote, even when they lived in enemy territory. They just did not talk about it beforehand.
You have heard the statement from politicians across the nation: the only poll that matters is the one on Election Day. How true that was in this presidential election.
 https://www.psychologytoday.com/blog/why-bad-looks-good/201608/admit-it-... . Some of the research in this article was originally cited there.
 Raymond J. La Raja, “Political Participation and Civic Courage: The Negative Effect of Transparency on Making Small Campaign Contributions,” Political Behavior Vo. 36 (2014):753–776 (757), DOI 10.1007/s11109-013-9259-8.
 La Raja, “Political Participation and Civic Courage,” 757.
 See generally, La Raja, “Political Participation and Civic Courage.”
 La Raja, “Political Participation and Civic Courage,” 754.
 James G. Gimpel, Joshua J. Dyck, and Daron R. Shaw, “Registrants, Voters, And Turnout Variability Across Neighborhoods,” Political Behavior, Vol. 26, No. 4, (2004): 343-375. (analysis of data from the 2000 Presidential election)
 La Raja, “Political Participation and Civic Courage,” 758.
 La Raja, “Political Participation and Civic Courage,” 758.