This article introduces the contributions to the PS Spotlight: The Collaborative Multiracial Post-Election Survey (CMPS) Oversamples. Each feature in this issue uses data from the 2020 CMPS to help us understand the strengths and limitations of survey oversamples and to discuss best practices for users of these data. The CMPS has changed the way data are collected and shared in the social sciences. It is a nonpartisan, cooperative, multiracial/ethnic, multilingual, post-presidential election online survey conducted in the United States. It was developed by political scientists in 2008. Beginning in 2016, these co-principal investigators (PIs) led an innovative cooperative funding strategy that broadened the scope of access to high-quality national survey data with large samples of racial/ethnic and underrepresented groups in the United States. See Barreto et al. (Reference Barreto, Frasure-Yokley, Vargas and Wong2018) for a comprehensive description of the CMPS survey design and methodology.
The 2020 CMPS featured six unique oversamples of minoritized populations in the United States. For many reasons, the need to oversample minoritized populations is more pressing than ever. Nevertheless, the experiences of these groups often are understudied and underexplored in social science research because traditional sampling methods cannot yield sufficient data for statistical analyses. The CMPS’s oversampling approach provides scholars with the sample size needed to conduct in-depth analyses. This can result in more comprehensive and inclusive findings, allowing researchers to understand more fully the attitudes, behaviors, and needs of underrepresented communities.
For many reasons, the need to oversample minoritized populations is more pressing than ever.
For the 2020 CMPS, we invited nine scholars to serve as Oversample Directors. They are experts in race, ethnicity, identity, and politics for the six unique oversamples, and include the following:
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• Afro-Latinos: Danielle Pilar Clealand (University of Texas at Austin)
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• Black Immigrants: Christina Greer (Fordham University) and Candis Watts Smith (Duke University)
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• LGBTQ+: Andrew Flores (American University)
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• Middle Eastern and North African (MENA)/Muslim Americans: Karam Dana (University of Washington Bothell) and Nazita Lajevardi (Michigan State University)
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• Native Americans: Raymond Foxworth (University of Colorado Boulder) and Laura Evans (University of California, Riverside)
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• Native Hawaiians: Ngoc Phan (Hawai‘i Pacific University)
Random probability sampling techniques of relatively small racial, ethnic, and other identity groups may not yield a sufficient sample size to allow researchers to conduct in-depth analysis of those groups. Survey oversamples allow researchers to select respondents so that some groups comprise a larger share of the survey sample than in the overall population (Mercer Reference Mercer2016). After data collection is complete, sampling weights are applied to the data to align the population with their actual proportion. The larger sample allows researchers to conduct more in-depth analysis of an individual group (Mercer Reference Mercer2016). The practice of oversampling groups that comprise a small proportion of the general population is expensive. Researchers often cannot afford the costs to carry out this sampling technique. Therefore, cooperative funding strategies remain important in building partnerships for scholars to collect survey oversamples.
This cooperative research model is user-content driven, whereas survey items included on the CMPS are generated through survey-question contributions from a national consortium called the CMPS Scholars Research Network. To date, this consortium includes almost 250 researchers from almost 100 accredited colleges and universities, across multiple academic disciplines, including the social sciences, psychology, public policy, public health, education, law, and other fields. With support from the National Science Foundation, the 2020 CMPS expanded in both size and content. It included a total of 14,977 completed interviews in the primary sample of Asian American, Black, Latinx, and White respondents. Table 1 presents the overall sample sizes of additional completed interviews with adults across various oversample groups from hard-to-reach populations. This includes Afro-Latinos, Black Immigrants, Native Americans, Native Hawaiians, Muslims (including MENA), and people who identify as LGBTQ+. The full dataset included 17,545 adult interviews. The invitation and the survey were available to respondents in English, Spanish, Chinese (simplified and traditional), Korean, Vietnamese, Arabic, Urdu, Farsi, and Haitian Creole.
Table 1 Overall Sample Sizes of the Adult Oversample

Source: 2020 Collaborative Multiracial Post-Election Survey Oversamples.
Because of the primary interest in the 2020 election, the project began with a large sample of registered voters from online sources that were pre-matched to the voter file. In addition, the data included a sample of nonregistered adults, including noncitizens. It is important to note that the 2020 CMPS also included a pilot sample of 16- and 17-year-old youth (N=1,457). The combined dataset was collected online in a respondent self-administered format from April 2 to October 4, 2021.
Understanding Oversample Categories and How Respondents Self-Identify
Oversample categories in table 1 are not mutually exclusive. The categories are based on respondent self-categorization and self-reporting. For example, respondents can be in the LGBTQ+ oversample as well as the American Indian oversample; the Afro-Latino oversample as well as the Black Immigrant oversample;. or the American Indian sample as well as the Hispanic/Latino oversample.
Throughout this project, the intention of CMPS co-PIs was to collect the most diverse sample of respondents in the United States as possible and to allow respondents to self-identify their race, ethnicity, and immigration status. The 2020 US Census revealed that the multiracial population (i.e., respondents who indicated two or more race categories) increased by 127% from 2010 to 2020. For 50 years in the US Census, Hispanic and Latino respondents were almost by definition “multiracial” or “multiethnic” because they answered both race and ethnicity questions. The outcome is that in both the real world and our data, respondents do not necessarily fit into clear or mutually exclusive categories. However, it also is the case that many respondents identify as single-race or monoracial.
For our overall project, we used several decisions in our initial categorization of respondents by race and ethnicity to meet minimum sample-size thresholds. Of course, end users can choose how to subset the data for analysis of different racial or ethnic groups. Therefore, we encourage individual researchers to be transparent in how they classify respondents in their analysis.
Overview of Featured Articles
This section presents the six insightful articles authored by the CMPS Oversample Directors. Ngoc Phan and Leilani DeLude’s discussion underscores the distinction among Native Hawaiians, Asian Americans, and Pacific Islanders in their racial, social, and legal position in American society. They emphasize factors that render recruitment difficult, including distrust of outsiders, contextual factors shaping self-identification, and geographic limitations of islands and the continental United States. They conclude by reviewing key findings from the 2020 CMPS Native Hawaiians oversample.
Danielle Pilar Clealand discusses the nuanced process of identifying Afro-Latinos, including measuring racial identity and blackness in a mixed-race population. The primary difficulty in data collection is the tension between participants’ self-identification and the racial frameworks of the United States, Latin America, and social sciences. Clealand describes the sociodemographic characteristics of the sample, such as whether respondents identify primarily as Latino or black and how that matters for identity politics.
Raymond Foxworth and Laura Evans (with Cheryl Ellenwood) examine the Native American oversample. Because there are 574 federally recognized sovereign tribes in the United States, the 2020 CMPS recognized the importance of capturing these communities’ unique political perspective. They describe the role of Native American identification, exploring participants’ sociodemographic characteristics and political attitudes, and conclude by discussing the challenges in obtaining Native American samples and future considerations.
Christina Greer and Candis Watts Smith note that the black population in the United States is ethnically diverse, from immigrant communities to second-generation Americans: 12% identifies as immigrants. They emphasize the need for black politics to expand to a more global perspective and the opportunities in the CMPS to do so. Challenges include differences in immigrant identification and country of origin that shape self-identification (e.g., a Black Immigrant or an Afro-Latino).
Nazita Lajevardi and Karam Dana highlight the importance of investigating MENA and Muslim perspectives in political science, given the increasing levels of Islamophobia and discrimination against these communities. Through the 2020 CMPS, they sought to address this need. They encountered several complications in recruiting participants due to distrust—particularly fear of surveillance and measurement issues for religious identification. Their best practices include a screener question about a respondent’s religion, a question about the faith group in which a participant was raised, development of a community sample for snowball sampling, and utilization of nonvoter lists.
In his article, Andrew Flores describes the need for large datasets in the study of LGBTQ+ politics, challenges in data collection, general findings, and takeaways for the 2024 CMPS. Given the lack of US Census data about the LGBTQ+ community, it is difficult to follow best statistical practices for stratification and weights. Moreover, the terms in the LGBTQ+ fluctuate changing accessibility terms in survey items. For future studies, he recommends including questions about sexual orientation and gender identity.
Conclusion
Since 2016, through research collaborations, conferences, workshops, and writing retreats, we have convened a diverse and multidisciplinary group of researchers in varying stages of their academic career. Using the collaborative, inclusive model of resource-sharing that we developed in 2016 and 2020, the 2024 CMPS will continue to expand research and professional-development opportunities for faculty; undergraduate and graduate students; and postdoctoral scholars from large research institutions, smaller liberal arts colleges, Historically Black Colleges and Universities, Tribal Colleges and Universities, and Hispanic Serving Institutions. This inclusive research and data-collection model will continue to highlight the voices of underrepresented groups in society and politics and also foster community among scholars in the social sciences and beyond.
ACKNOWLEDGMENT
The authors acknowledge the support of the National Science Foundation Award No. 1918510.
DATA AVAILABILITY STATEMENT
The 2020 Collaborative Multiracial Post-Election Survey is available at the Inter-University Consortium for Political and Social Research (https://doi.org/10.3886/ICPSR39096.v1).
CONFLICTS OF INTEREST
The authors declare that there are no ethical issues or conflicts of interest in this research.