A new study published in the Journal of Experimental Political Science suggests that Americans’ attitudes toward immigration are shaped not only by cultural or economic concerns but also by their beliefs about how immigrants vote. When Americans were told that certain immigrant groups favored Donald Trump and the Republican Party, Republicans became more supportive of immigration, while Democrats grew less supportive. These results suggest that perceptions of immigrants’ political preferences can influence support for immigration in ways that reflect broader partisan dynamics.
Public opinion on immigration in the United States tends to be deeply divided along party lines. Democrats are generally more supportive of increased immigration, while Republicans often take a more restrictive stance. Scholars have long examined how economic competition, cultural identity, and national security concerns contribute to these divisions. However, this study explores a different angle. It asks whether partisan assumptions about immigrants—specifically, beliefs about which political party they support—affect how Americans feel about letting more immigrants into the country.
There is a widespread perception in the United States that immigrants tend to vote for Democrats. This belief has been echoed in both mainstream media and right-wing commentary, and it has led some to claim that immigration benefits the Democratic Party at the ballot box. The authors of the study, Daniel McDowell of Syracuse University and David A. Steinberg of Johns Hopkins University, sought to test whether these assumptions shape people’s views about immigration policy.
“The way that immigrants are often portrayed as reliable Democratic voters is really what drew us to the topic,” explained McDowell, the Maxwell Advisory Board Professor of International Affairs. “This perception seemed to animate some of the resistance to immigration on the U..S political right, especially because more immigration would then result in diminished electoral success for Republicans down the road. We similarly wondered if some share of pro-immigration sentiment on the political left reflected the belief that new arrivals were essentially co-partisans, and that immigration could eventually bring about a permanent Democratic majority.”
To investigate this question, the researchers embedded a preregistered experiment in a nationally representative survey of 3,000 American adults. The survey was conducted in the final week before the 2024 United States presidential election. Participants were recruited through Dynata, a survey firm, and the sample was designed to reflect the general population in terms of age, gender, and education level.
The experiment focused on immigrants from two countries (Venezuela and Vietnam) because data from previous elections suggested that many immigrants from these countries had shifted toward supporting Donald Trump. Participants were randomly assigned to one of two groups. The control group received basic information about immigration from one of the two countries. The treatment group received the same information, but with an added sentence stating that most immigrants from that country support Donald Trump and the Republican Party.
After reading this information, respondents were asked whether they agreed or disagreed that the United States should allow more immigration from that country. They answered using a scale from zero to ten, with higher numbers indicating more support.
The study also included a follow-up question asking respondents whether they believed immigrants from the country they had just read about would support Trump or his Democratic opponent, Kamala Harris. This question helped the researchers determine whether the treatment successfully shifted perceptions of immigrants’ political leanings.
The results show that most Americans in the control group (who received no political information about immigrants) assumed that migrants from Venezuela or Vietnam would vote for the Democratic candidate, Kamala Harris. Nearly 80 percent of respondents in this group expected migrants to support her, compared to just 20 percent who believed they would back Trump.
In the treatment group, this pattern flipped. About 62 percent of those who were told that migrants supported Trump believed those immigrants would vote Republican. This suggests that the treatment worked as intended and successfully changed respondents’ beliefs about immigrant political preferences.
These changing perceptions had a strong effect on people’s views about immigration. In the control group, Democrats were the most supportive of increased immigration, giving an average score of 5.3 on the 10-point scale. Independents averaged 4.2, and Republicans just 3.0. These results are consistent with long-standing partisan divides on immigration.
But in the treatment group, where respondents were told that immigrants favored Trump, those divides disappeared. Republican support for immigration rose to an average score of 4.3. Meanwhile, Democratic support dropped to 4.4. This near-convergence indicates that beliefs about how immigrants vote can override traditional partisan divides on immigration.
“We were confident that the treatment effect would work as we expected, given the partisan nature of most issues in the United States today,” McDowell told PsyPost. “However, the size and durability of the treatment effect, conditional on party ID, across two culturally distinct immigrant groups was a bit surprising. In a sense, I guess you could say the treatment worked better than even we anticipated.”
The study also found that the effects were most pronounced among strong partisans. Republicans and Democrats who identified strongly with their party were more responsive to the treatment than those who considered themselves weak partisans. Independents, by contrast, were not significantly influenced by the treatment. Their average levels of support for immigration remained the same, whether or not they were told that immigrants favored Trump.
Importantly, the effects of the treatment were similar across both immigrant groups. Whether participants were asked about Venezuelan or Vietnamese immigrants, the direction of the effect stayed the same. However, all respondents were somewhat more favorable toward Vietnamese immigrants overall, a pattern that aligns with previous research suggesting Americans tend to prefer immigrants from certain regions or countries.
The researchers also explored whether political ideology, such as identifying as liberal or conservative, explained the results. Although ideology did influence responses to some degree, partisanship was a stronger predictor of how participants reacted to the information.
“Immigration attitudes are not immune to strategic electoral thinking and hyper-partisanship,” McDowell explained. “For many Americans, our study shows that the desirability of immigration depends not just on cultural or economic factors, but also whether voters believe migrants have the same partisan preferences that that they do.”
“Our findings will only have practical significance if Americans’ beliefs about immigrants’ partisan identities moves away from the status quo. If the underlying beliefs do not change, then our results will not be predictive of future shifts in immigration attitudes. On the other hand, if Americans begin to view immigrants as politically neutral, or even in some cases, likely Republican voters, then we would expect to see some convergence — or de-polarization — between Democratic and Republican voters on the issue. This is precisely what our results show. While it is too soon to tell if this is occurring, it is something to keep an eye on.”
Although the study provides clear evidence that Americans’ immigration views are shaped by their perceptions of immigrants’ political preferences, it has several limitations.
First, the researchers focused only on legal immigration. It remains uncertain whether similar results would appear when asking about unauthorized immigration or border enforcement, which are often more controversial topics. The study also asked only about immigration from two countries, which may not capture the full range of public opinion on immigration from other parts of the world.
Second, the researchers did not include a treatment where immigrants were described as supporting the Democratic Party. They made this decision because most Americans already assume that immigrants vote Democratic, but future studies could still explore how this assumption plays out when it is made explicit.
The study also cannot conclusively determine whether the observed effects are due to strategic thinking, personal affinity for like-minded individuals, or some combination of the two. More research is needed to better understand why people prefer immigrants who share their political views.
The study, “Do Immigrants’ Partisan Preferences Influence Americans’ Support for Immigration?,” was published September 1, 2025.
