Why do unmarried women tend to be more liberal and Democratic than their married counterparts? A key reason is because unmarried women -- those who have never been married and those who are divorced -- are more concerned about the status of women as a collective group according to survey results presented at the 110th Annual Meeting of the American Sociological Association. 

These results reveal that unmarried women have high levels of "linked fate," or the conviction that an individual's chances of success depend on the status of the group. According to Kelsy Kretschmer, a co-author of the study and an assistant professor of sociology at Oregon State University, the differences in married and unmarried women's levels of gender "linked fate" explain a significant amount of their political divergence.

"Over 67 percent of never married women and 66 percent of divorced women perceive what happens to other women as having some or a lot to do with what happens in their own lives," said Kretschmer. "Only 56.5 percent of married women hold the same views.

"For a woman, when it comes to politics, having a high level of gender linked fate generally means she thinks in terms of what will benefit women as a group. This could encompass things such as wage equality, workplace protections for pregnancy and maternity leave, anti-domestic violence laws, and welfare expansion. Not every individual woman needs these things, but women who have a strong sense of gender-linked fate will think in terms of how women as a group will benefit from them. These issues have been most championed in the United States by liberals, female representatives, and the Democratic Party."

Confirming their prior beliefs and well-known political statistics, Kretschmer,  Christopher Stout, an assistant professor of political science at Oregon State University, and Leah Ruppanner, an assistant professor in the School of Social and Political Science at the University of Melbourne, say that never married and divorced women are more likely to be Democrats than married women. They also found married women are less likely to believe that gender is most important in elected positions. 

The paper relied on survey data from the nationally representative 2010 American National Election Study (ANES), which asked a wide range of questions about political attitudes and behaviors. The three researchers compared the responses of married, never married, divorced, and widowed women 18 years of age and older.

Widowed women and married women are nearly identical to each other when it comes to their belief in gender linked fate. 

"Widowed women are frequently older and never ruptured their relationships with their husbands by divorcing them," Kretschmer said. "They may still be receiving their husbands' pensions, social security, or health benefits. In other words, despite not having a husband, many widows are still engaged in the marriage institution in ways that make them more like married women than never married or divorced women."

According to Kretschmer, the concept of linked fate has previously been used to understand why African Americans and Latinos "are more likely than other underrepresented groups to vote in blocs for candidates, parties, and policies that will benefit the majority of the group, even if not the individual voter." 

The researchers found that differences in married and unmarried women's income, employment status, etc. do not explain the marriage gap in political preferences.

"We were surprised because these are the traditional explanations for why married women are more conservative and Republican," said Kretschmer. "However, we found that whether or not a woman has a sense of linked fate with other women does a better job than any of these previously considered variables of explaining why the marriage gap exists, and yet no one is talking about this as an important factor in women's political preferences."

But, perhaps that needs to change. As women increasingly get married later or do not marry, Kretschmer said, more unmarried women may amount to more support for liberal and Democratic candidates and policies, as well as for female political candidates. Or sociologists may learn that getting married is not a gender-linked fate to becoming Republican.