Donald Trump's early electoral success has exceeded the expectations of virtually everyone. His success among a number of constituencies with varying interests invites the question: How does someone known to clearly switch his positions within an hour-long debate, who has virtually no political experience, and who brags about the size of his biological features gain this much traction with voters?

A number of explanations have been proposed. Individuals who score high on authoritarianism, a personality trait that indicates a psychological preference for order and a fear of outsiders, helps explain Trump support. So, too, does white identity. Hostility toward out-groups, coupled with the perception that government is increasingly discriminatory toward whites, offers considerable insight into individual voting intentions.

These explanations all hold merit but, on their own, may be incomplete. Instead, our research predicts that as individuals' social and political identities converge (or become "sorted"), support for someone like Donald Trump is predictable — particularly when you consider that most Republicans are not orthodox ideologues. In fact, given what we know about the structure of belief systems, namely that the average voter holds a considerable number of policy preferences that are paradoxical, this social sorting offers an explanation for Trump's support that draws on the power of group attachments.

In a primary race where the main narrative seems to be that the Republican Party is being broken into pieces, recent data from the first wave of the American National Election Studies 2016 Pilot Study suggests that this division is not the source of Trump's support. In fact, it appears Trump is popular despite the splintering of the Republican Party.

We find that the three major components of the modern Republican Party (traditional Republicans, conservative Christians, and white identifiers) are most likely to predict Trump support when these separate identities are working together. So, in a sense, Trump's support isn't an anomaly of Republican splintering — it's the natural outcome of these identities that have been coalescing over time. Thus, for many Republicans who strongly identify with one group (i.e., Republican) but not another (i.e., white), this primary season may feel alienating and frustrating, but for those who strongly identify with all three of these groups, Trump is their guy.

When we look at the "affect" or feelings toward the three front-running Republican candidates, we find that "feeling thermometer" ratings, or descriptions of how warm or cool someone feels toward a candidate, are related to the alignment of a person's Republican, racial (white), and religious (Christian) identities. When a person does not strongly identify with all three social groups, she feels quite negative toward Trump. However, when all three identities are well-sorted, Trump benefits more than either Ted Cruz or Marco Rubio.

Moreover, not only do such individuals feel more positive about Trump, but they are also far more likely to vote for him.

Social psychology research has found that when most of the members of one social group are also members of another social group, those who identify with both groups are more likely to view outsiders with intolerance and to see them as very different from themselves. Once people feel so isolated from outsiders, for example, they are more sensitive to threats from these potential enemies, and they are more easily angered by threats from anyone who is not in the group.

In other words, the more our identities are aligned, the more foreign any outsider will seem, regardless of logical reasoning (or, perhaps, policy preferences). These sentiments are familiar from Trump's supporters, and the effect of combining these identities may fit perfectly with a Trump candidacy, as he speaks directly to the anger and intolerance that are results of this type of social sorting.

These angry and intolerant responses, however, should be the most concentrated among those who are in a perpetual state of feeling like their status is being threatened. This is because social identities provide people with a sense of esteem that they may not be capable of getting from their own individual lives. When their group wins, they feel like winners, even if they are not winners on their own.

In order to examine this feature of the groundswell of Trump support, we split the sample into "poor" (the people facing the most status threat in their lives in general, coded as the bottom fifth of self-reported income distribution within the ANES sample) and "not poor."

It turns out that support for Trump is most powerful among those identifying as Republican, religious, white, and poor. This "coalition" built by the Republican Party is particularly strong among the poorest voters, ostensibly because they feel the most status threat and therefore are the ones who most desperately need a sense of group victory. (In effect, this cleavage may be emblematic of the awkward relationship between Dixiecrats and the larger GOP.) They therefore respond most strongly to their religious, partisan, and racial identities by voting for Trump (who makes them feel most empowered and is the most aggressive attacker of outsiders).

According to these results, Trump is capable of capturing the imaginations of well-sorted poor voters far more effectively than either Cruz or Rubio can. Not only do poor voters feel the most warmly toward Trump, as shown in their "thermometer" ratings, but they are also far more likely to vote for him.

These results call into question the idea that Trump is only garnering the votes of poor white people. In fact, he is winning the votes of poor, white, religious Republicans better than either Cruz or Rubio. This could also help explain why Cruz has been performing well in caucus states, where the cost of participation is high and poorer voters have less of a voice.

As we see it, Trump is likely to remain a formidable candidate, as long as he provides a strong identity for those who need to buttress their sense of victory in their own lives by gathering their group identities around themselves. As the primary season wears on, this social sorting is likely to further push the well-sorted in the direction of Trump as questions of viability threaten the other candidates.

Lilliana Mason is an assistant professor of government and politics at the University of Maryland College Park.

Nicholas Davis is a doctoral candidate in political science at Louisiana State University.