¹ Berelson, Bernard R., Lazarsfeld, Paul F.McPhee, and William N., Voting: A Study of Opinion Formation in a Presidential Campaign (Chicago: University of Chicago Press, 1954)Google Scholar.

² Huddy, Leonie, ‘From Social to Political Identity: A Critical Examination of Social Identity Theory’, Political Psychology, 22 (2001), 127–156CrossRefGoogle Scholar.

³ In this article, I use the terms ‘lesbian, gay and bisexual’ and ‘gay’ interchangeably.

⁴ Edelman, Murray S., ‘Understanding the Gay and Lesbian Vote in '92’, Public Perspective, 4 (1993), 32–33Google Scholar; Egan, Patrick J. and Sherrill, Kenneth, ‘Marriage and the Shifting Priorities of a New Generation of Lesbians and Gays’, PS: Political Science and Politics, 38 (2005), 229–232Google Scholar; Lewis, Gregory B.Rogers, Marc A. and Sherrill, Kenneth, ‘Lesbian, Gay, and Bisexual Voters in the 2000 Election’, Politics and Policy, 39 (2011), 655–677CrossRefGoogle Scholar; Schaffner, Brian and Senic, Nenad, ‘Rights or Benefits? Explaining the Sexual Identity Gap in American Political Behavior’, Political Research Quarterly, 59 (2006), 123–132CrossRefGoogle Scholar; Sherrill, Kenneth, ‘The Political Power of Lesbians, Gays and Bisexuals’, PS: Political Science and Politics, 29 (1996), 469–473Google Scholar; Smith, Raymond A. and Haider-Markel, Donald P., Gay and Lesbian Americans and Political Participation: A Reference Handbook (Santa Barbara, Calif.: ABC-CLIO Press, 2002)Google Scholar.

⁵ Bailey, Robert W., Gay Politics, Urban Politics: Identity and Economics in the Urban Setting (New York: Columbia University Press, 1999)Google Scholar; Hertzog, Mark, The Lavender Vote: Lesbians, Gay Men and Bisexuals in American Electoral Politics (New York: NYU Press, 1996)Google Scholar.

⁶ Similar results were yielded by an individual-level analysis consisting of a regression of vote choice on gay identity, the difference in candidates’ gay-rights roll-call scores, and the interaction of these two variables, which failed to reject the null hypothesis that gay voters’ choices are unaffected by the candidates’ stances on gay rights.

⁷ LeVay, Simon, ‘A Difference in the Hypothalamic Structure between Heterosexual and Homosexual Men’, Science 253 (1991), 1034–1037CrossRefGoogle Scholar; Lalumière, Martin L.Blanchard, Ray and Zucker, Kenneth J., ‘Sexual Orientation and Handedness in Men and Women: A Meta-Analysis’, Psychological Bulletin 126 (2000), 575–592CrossRefGoogle Scholar; Klar, Amar J. S., ‘Excess of Counterclockwise Scalp Hair-Whorl Rotation in Homosexual Men’, Journal of Genetics, 83 (2004), 251–255CrossRefGoogle Scholar.

⁸ Cass, Vivienne C., ‘Homosexual Identity Formation: Testing a Theoretical Model’, Journal of Sex Research, 20 (1984), 143–167CrossRefGoogle Scholar; Troiden, Richard, ‘The Formation of Homosexual Identities’, Journal of Homosexuality, 17 (1989), 43–73CrossRefGoogle Scholar.

⁹ Greenberg, David Frank, The Construction of Homosexuality (Chicago: University of Chicago Press, 1988)Google Scholar.

¹⁰ D'Emilio, John, Sexual Politics, Sexual Communities: The Making of a Homosexual Minority in the United States, 1940–1970 (Chicago: University of Chicago Press, 1983)Google Scholar.

¹¹ Laumann, Edward O., Gagnon, John H.Michael, Robert T. and Michaels, Stuart, The Social Organization of Sexuality: Sexual Practices in the United States (Chicago: University of Chicago Press, 1994)Google Scholar; Mosher, William D.Chandra, Anjani and Jones, Jo, ‘Sexual Behavior and Selected Health Measures: Men and Women 15–44 Years of Age, United States, 2002’, Advance Data from Vital and Health Statistics, 362 (15 September 2005)Google Scholar; Pathela, Preeti, Hajat, Anjum, Schillinger, Julia, Blank, SusanSell, Randall and Mostashari, Farzad, ‘Discordance between Sexual Behavior and Self-Reported Sexual Identity: A Population-Based Survey of New York City Men’, Annals of Internal Medicine, 145 (2006), 416–425CrossRefGoogle Scholar.

¹² The true differences in background characteristics may be larger than those shown here, as social desirability effects almost surely cause same-sex sexual partners to be underreported to the GSS. To the extent that this underreporting is predicted with the background characteristics listed in Table 2, this would bias against the finding of significant differences with regard to these variables between identifiers and non-identifiers.

¹³ Berelson, Lazarsfeld and McPhee, Voting.

¹⁴ Centers, Richard, The Psychology of Social Classes (Princeton, N.J.: Princeton University Press, 1949)Google Scholar.

¹⁵ Schur, LisaShields, Todd and Schriner, Kay, ‘Generational Cohorts, Group Membership and Political Participation by People with Disabilities’, Political Research Quarterly, 58 (2005), 487–496CrossRefGoogle Scholar.

¹⁶ For a thorough review of this literature, see Huddy, Leonie, ‘Group Identity and Political Cohesion’, in David O. Sears, Leonie Huddy and Robert Jervis, eds, Oxford Handbook of Political Psychology (New York: Oxford University Press, 2003), pp. 511–558Google Scholar.

¹⁷ Conover, Pamela Johnston, ‘The Influence of Group Perceptions on Political Perception and Evaluation’, Journal of Politics, 46 (1984), 760–785CrossRefGoogle Scholar; Dawson, Michael C., Behind the Mule: Race and Class in African-American Politics (Princeton, N.J.: Princeton University Press, 1994)Google Scholar; Tate, Katherine, From Protest to Politics: The New Black Voters in American Elections (New York: Russell Sage Foundation and Cambridge, Mass.: Harvard University Press, 1993)Google Scholar.

¹⁸ Citrin, JackWong, Cara and Duff, Brian, ‘The Meaning of American National Identity: Patterns of Ethnic Conflict and Consensus’, in Richard D. Ashmore and Lee Jussim, eds, Social Identity, Intergroup Conflict, and Conflict Reduction (New York: Oxford University Press, 2001)Google Scholar; Breakwell, Glynis M. and Lyons, Evanthia, Changing European Identities: Social Psychological Analyses of Social Change (Oxford: Butterworth-Heinemann, 1996)Google Scholar.

¹⁹ Kinder, DonaldAdams, Gordon S. and Gronke, Paul, ‘Economics and Politics in the 1984 Presidential Election’, American Journal of Political Science, 33 (1989), 491–515CrossRefGoogle Scholar; Miller, Arthur H., Gurin, PatriciaGurin, Gerald and Malanchuk, Oksana, ‘Group Consciousness and Political Participation’, American Journal of Political Science, 25 (1981), 494–511CrossRefGoogle Scholar; Tate, From Protest to Politics.

²⁰ Hertzog, The Lavender Vote, p. 36Google Scholar.

²¹ Bailey, Gay Politics, Urban Politics, p. 132Google Scholar.

²² Sherrill, ‘The Political Power of Gays, Lesbians, and Bisexuals’, p. 472Google Scholar. For demographic data on residential concentration of LGBs, see Gates, Gary J. and Ost, Jason, The Gay and Lesbian Atlas (Washington, D.C.: The Urban Institute Press, 2004)Google Scholar.

²³ Schaffner and Senic, ‘Rights or Benefits?’

²⁴ Lewis, Rogers, and Sherrill, ‘Lesbian, Gay, and Bisexual Voters in the 2000 Election’.

²⁵ Angus Campbell, Philip E. Converse, Warren E. Miller and Donald E. Stokes, The American Voter, Unabridged edn (New York: John Wiley and Sons, 1960), p. 323Google Scholar.

²⁶ See, for example, Gelman, Andrew and Hill, Jennifer, Data Analysis Using Regression and Multilevel/ Hierarchical Models (New York: Cambridge University Press, 2006)CrossRefGoogle Scholar, pp. 188–190.

²⁷ Goodness of fit statistics reported in Table 3 (expected percentage correctly predicted and expected proportional reduction in error) are calculated as proposed in Herron, Michael C., ‘Postestimation Uncertainty in Limited Dependent Variable Models’, Political Analysis, 8 (1999), 83–98CrossRefGoogle Scholar, and implemented by the epcp routine in Stata (Christopher N. Lawrence, ‘epcp: Display Classification Accuracy for Nonmetric Dependent Variable Models’, 2009, available at www.cnlawrence.com/data/epcp.zip).

²⁸ The null hypothesis that these two predictions are equal is rejected at p = 0.03 (two-tailed test).

²⁹ See for example Ho, Daniel E., Imai, KosukeKing, Gary and Stuart, Elizabeth A., ‘Matching as Nonparametric Preprocessing for Reducing Model Dependence in Parametric Causal Inference’, Political Analysis, 15 (2007), 199–236CrossRefGoogle Scholar; Imbens, Guido and Wooldridge, Jeffrey M., ‘Recent Developments in the Econometrics of Program Evaluation’, Journal of Economic Literature, 47 (2009), 5–86CrossRefGoogle Scholar.

³⁰ In the present context, the average treatment effect, or ATE, is the proper quantity of interest as we are simply interested in the average differences in political views remaining between gays and straights after accounting for the fact that they come from dissimilar backgrounds. In the literature on program evaluation, the ATE has at times been criticized as an estimand, because it compares those treated with the entire population – including those individuals who would never be eligible for the ‘treatment’ of participation in the program. In the present context, however, there is no reason to rule out any identifiable subset of the population. Those eligible for treatment are people with the ascriptive trait of same-sex attraction – a trait we assume is not predictable with the background characteristics in Table 4.

³¹ Imbens and Wooldridge, ‘Recent Developments in the Econometrics of Program Evaluation’, pp. 40–41Google Scholar.

³² Because LGB respondents in the GSS are vastly outnumbered by the non-LGB respondents, in practice this means that some LGB respondents are repeatedly matched to multiple non-LGBs. Compared to matching without replacement this technique generally lowers the bias of estimates while increasing their variance. See Abadie, Alberto and Imbens, Guido W., ‘Large Sample Properties of Matching Estimators for Average Treatment Effects’, Econometrica, 74 (2006), 235–267CrossRefGoogle Scholar. Software used for these estimates: Abadie, Alberto, Herr, Jane LeberImbens, Guido W. and Drukker, David M., ‘NNMATCH: Stata Module to Compute Nearest-Neighbor Bias-Corrected Estimators’, 2004, available at http://ideas.repec.org/c/boc/bocode/s439701.htmlGoogle Scholar.

³³ Diamond, Alexis and Sekhon, Jasjeet, ‘Genetic Matching for Estimating Causal Effects: A General Multivariate Matching Method for Achieving Balance in Observational Studies’ (unpublished, University of California, Berkeley, 2010)Google Scholar. Software used for these estimates: Sekhon, Jasjeet S., ‘Multivariate and Propensity Score Matching Software with Automated Balance Optimization: The Matching Package for R’, Journal of Statistical Software, 42 (2011:7), 1–52CrossRefGoogle Scholar.

³⁴ Statistical significance is assessed using one-tailed difference-of-means hypothesis tests, which reflect the strong theoretical expectation that gay–straight differences should be diminished after accounting for background characteristics. I refrain from making explicit comparisons regarding the relative size of selection effects among the dependent variables as the sampling distributions of these ratios are unknown without making additional assumptions.

³⁵ Green, DonaldPalmquist, Bradley and Schickler, Eric, Partisan Hearts and Minds: Political Parties and the Social Identities of Voters (New Haven, Conn.: Yale University Press, 2004)Google Scholar; Richard G. Niemi and M. Kent Jennings, ‘Issues and Inheritance in the Formation of Party Identification’, American Journal of Political Science, 35 (1991), 970–988CrossRefGoogle Scholar; Stoker, Laura and Jennings, M. Kent, ‘Of Time and the Development of Partisan Polarization’, American Journal of Political Science, 52 (2008), 619–635CrossRefGoogle Scholar.

³⁶ Achen, Christopher H., ‘Parental Socialization and Rational Party Identification’, Political Behavior, 24 (2002), 151–170CrossRefGoogle Scholar.

³⁷ There are approximately 1,100 American adults per voting precinct, according to a ratio constructed with the following figures. In 1990, the national voting-age population was 185.5 million people (Statistical Abstract of the United States: 2007 (Washington D.C.: U.S. Census Bureau, 2006), p. 12). In that same year (the most recent for which data are available), there were about 170,000 election precincts nationwide ( King, Gary and Palmquist, Bradley, ‘The Record of American Democracy, 1984–1990’, PS: Political Science and Politics, 30 (1997), 746–747Google Scholar).

³⁸ Unfortunately, the data and specifications used here make the matching analyses in Table 5 infeasible.

³⁹ Giddens, Anthony, Modernity and Self Identity: Self and Society in the Late Modern Age (Stanford, Calif.: Stanford University Press, 1991)Google Scholar.

⁴⁰ Another important explanation for how group cohesion develops comes from social identity theory, which has found that in-group favouritism can arise under highly artificial and minimal conditions ( Henri Tajfel, Human Groups and Social Categories (Cambridge: Cambridge University Press, 1981Google Scholar); Turner, John C., Rediscovering the Social Group: A Self-Categorization Theory (Oxford: Blackwell, 1987)Google Scholar). However, like the work on mobilization, this line of research has yet to explore in detail the identity selection process discussed here (see Huddy, ‘From Social to Political Identity’).

⁴¹ Frymer, Paul, Uneasy Alliances: Race and Party Competition in America (Princeton, N.J.: Princeton University Press, 1999)Google Scholar; Frymer, Paul and Skrentny, John David, ‘Coalition Building and the Politics of Electoral Capture during the Nixon Administration: African Americans, Labor, Latinos’, Studies in American Political Development, 12 (1998), 1313–1361CrossRefGoogle Scholar; Smith, Charles Anthony, ‘The Electoral Capture of Gay and Lesbian Americans: Evidence and Implications from the 2004 Election’, Studies in Law, Politics and Society, 40 (2007), 103–121CrossRefGoogle Scholar.

⁴² Lax, Jeffrey R. and Phillips, Justin H., ‘Gay Rights in the States: Public Opinion and Policy Responsiveness’, American Political Science Review, 103 (2009), 367–386CrossRefGoogle Scholar; Mucciaroni, Gary, Same Sex, Different Politics: Success and Failure in the Struggles over Gay Rights (Chicago: University of Chicago Press, 2008)CrossRefGoogle Scholar.

⁴³ Cook, Timothy E., ‘The Empirical Study of Lesbian, Gay and Bisexual Politics: Assessing the First Wave of Research’, American Political Science Review, 93 (1999), 679–692CrossRefGoogle Scholar, p. 691.