A woman waits to cast her ballot for the presidential primary in Canterbury, N.H., on Feb. 9, 2016. (Jewel Samad/AFP/Getty Images)

On Monday, an unseen cosmic gauge will tick one notch closer to 100 percent. Cindy Hyde-Smith, agriculture commissioner of Mississippi, will be sworn in as the state’s junior senator. Hyde-Smith is Mississippi’s first woman to serve as senator, appointed to fill the remainder of the term won by Thad Cochran (R).

With her swearing-in, Mississippi becomes the 30th state to have been represented by a woman in the upper chamber. In recent years, women have more frequently joined the Senate for the first time from their states after having won elections rather than being appointed.


The Senate will be almost a quarter female after her swearing-in, while women make up almost a fifth of the House. That’s not representative of the percentage of women in America, but it’s better than even just 20 years ago, at which point only 16 states had been represented in the Senate by women.

Earlier this week, the Associated Press noted that a record number of women were hoping to similarly earn spots in Congress. Using data from the Center for American Women and Politics, the AP determined that more women had filed to run for Congress than in any election year since 1992. In total, 309 women have thrown their hats into the ring so far in 2018, 231 of them Democrats and 78 Republicans. (The next-highest number of female candidates was in 2012, when 298 House candidates were women.)

The number of women running for the Senate isn’t a record; that was set in 2016 at 40. Nonetheless, 13 Republican women and 17 Democratic women have declared their candidacies.


Those tallies are particularly interesting given research released this week by Barry Burden of the University of Wisconsin in Madison and Yoshikuni Ono of Tohoku University in Japan. They analyzed the extent to which gender bias affected the underrepresentation of women in elected office using a survey that presented respondents with randomly generated fictional candidates.

A central finding was that gender did play a role in how likely a respondent was to pick a candidate, but within particular boundaries. When considering a gubernatorial or state legislative general election (where the parties of the fictional candidates were different), there was no significant difference in preferences between males and females from respondents who were Democrats, Republicans or independents. But in the primaries, where there was no partisan difference, Democrats preferred female candidates — and Republicans preferred men.


This new study follows up on one from last year, in which Burden and Ono assessed attitudes about presidential and congressional candidates. In that case, the researchers determined that there was only a small difference between support for men and women among Democrats, but that Republicans were more likely to support a male candidate in party primaries.


Why? Burden and Ono offer a hypothesis.

“Candidate sex is likely to operate differently in a primary where voters make choices between two competing candidates of the same party. For Democrats, candidate sex does not convey as a clear ideological signal; thus, the effect of candidate sex is expected to be marginal regardless of a candidate’s party label. In contrast, Republicans tend to view female candidates [as] more liberal than comparable male candidates, which might lead them to withdraw their support to female candidates unless a party signal differentiates the two competing candidates.”

The pair found that the effect of gender bias was stronger in presidential races than congressional, perhaps because voters are familiar with women having served in Congress. But it raises an interesting question: Does the theory presented above about Republican bias help explain why more of the women serving in Congress are Democrats?

The CAWP data for 2018 shows that 10 percent of the women who filed to run as Democrats in the House have lost compared with 11.5 percent of the Republican women. Nearly 8 percent of the Democratic women have won, compared with about 3 percent of Republican women who declared their candidacies.


These figures include incumbents, though, and of the 70 incumbent women running in 2018, 54 are Democrats.

The more immediately obvious reason that more of the women in Congress are Democrats is that more women run as Democrats. Last month, Pew Research Center released analysis of partisan identification by various demographics, including gender. Women are much more likely to be Democrats (or to lean to the Democratic Party) than to be or lean toward the Republicans.


Of the 20 states that haven’t had a woman serve as senator, eight voted for Hillary Clinton in 2016 while 12 backed Donald Trump. That’s 40 percent of each group: 40 percent of Clinton states and 40 percent of Trump states.

After Monday only one state will have never had a woman represent it at the federal level.

That state is Vermont.