In state after state, a recurrent question of the 2016 campaign has been how much two powerful social forces, economic anxiety and racial anxiety, are driving support vote for Donald Trump. There is a good deal of evidence that both factors are at play in the Republican presidential primary races.But a crucial unanswered question concerns how these two forces interact. Are Trump's supporters mainly motivated by a shared concern about white status and identity? Or are economic concerns the basis of Trump's support?To investigate the relationship between these factors, the Washington Post and ABC News asked several new questions in a national poll earlier this month.Among many other topics, respondents were asked whether they were struggling economically — or whether they were comfortable and moving up. They were also asked whether they thought it was more of a problem that African-Americans and Latinos are "losing out because of preferences for whites" or whether whites are "losing out because of preferences for blacks and Hispanics." The survey asked this question in order to gauge the sentiment that racial and ethnic groups don't just feel they are facing difficulties in general, but that those losses are being caused by other group's gains.All in all, the results suggest that both economic and racial anxieties are driving supporters to Trump. To learn more about the connection between these two kinds of concerns, the Post performed a series of statistical tests on the data.Republicans who are worried about maintaining their economic situation are more likely to support Trump, regardless of whether they think that whites losing out to other groups is a big problem. Likewise, those who feel that whites are losing out are more likely to support Trump regardless of their level of economic anxiety. The analysis took both factors into account, and also controlled for demographics, income and political ideology.Those who voiced concerns about white status appeared to be even more likely to support Trump than those who said they were struggling economically, but the results did not clearly show which concern was more important among Trump's coalition. That's akin to when a candidate is leading another candidate in a poll, but the lead is within the poll's margin of error. In addition, the Post tested the direct connection between whether Republican-leaning respondents said that they were struggling economically and whether they said that whites are losing out to other groups, and found the correlation was weak.None of these measures is perfect, of course. And these are only two of many factors behind Trump's support, according to analysis of the Post -ABC data. Controlling for multiple demographic factors and the above attitudes, men, for instance, were significantly more likely to support Trump. White respondents without college degrees were also especially supportive, as were Republicans who do not identify as white evangelical Protestants. Republicans who felt "strongly" that the political system is dysfunctional were more likely to support Trump even when controlling for other factors.Max Ehrenfreund writes for the Washington Post's Wonkblog. Scott Clement is the polling manager at the Post, specializing in public opinion about politics, election campaigns and public policy.© 2016 Washington Post