This map shows the number of women in every state legislature

The number of women serving on state legislatures in the U.S. has stagnated in recent years, in part because of factors that discourage women to run for office, studies suggest.

Nationally, women make up about a quarter of the seats on state legislatures, a number that has mostly leveled off since 1999 after a period of rapid rise beginning in the 1970s started to close the gap.

Colorado and Vermont have the largest percentage of women serving on their state legislatures at 41 percent, while Louisiana has the fewest, with 12 percent of seats held by women.

A Pew Charitable Trust study released last year found that women are less likely to seek office, are often not recruited by male-dominated political committees and may not have crucial access to funding to the extent that male candidates seeking office do.

Katie Ziegler, of the National Conference of State Legislatures, said while women tend to win at the same rate as men, a leading cause for the disparities comes down to participation. A 2012 study called “Men Rule: The Continued Under-Representation of Women in U.S. Politics” found that “no differences emerge in women and men’s fundraising receipts, vote totals, or electoral success.”

“The really fundamental reason is because women are not running for these legislative seats,” Ziegler said. “It’s not any ballot box bias but it’s making the decision to become a candidate.”

More Democratic than Republican women hold state office

According to the Pew study and interviews with research institutions that track statistics on women in politics, the number of women in office also differs by party lines.

A total of 60 percent of female state legislators come from the Democratic Party and 40 percent from the Republican Party. More than 33 percent of Democratic seats and 20 percent of Republican seats are filled by women, Pew said.

“Republican gains at the state level over the past decade may be one reason the overall percentage of women in state legislatures has been stuck at 25 percent,” according to the Pew study.

Child care responsibilities, bias against women candidates and increasingly pernicious partisan politics may also be factors leading fewer women to seek office, Ziegler said.

A survey conducted by the Rutgers University Center for American Politics asked male and female politicians about their motivations to seek office and found that women were more likely to run after being encouraged or recruited by someone in power.

“Somebody demonstrated to them that they had a real chance, that they had powerful people behind them,” Kelly Dittmar, a professor at the center, said.

A Princeton University study found that women are often less involved in policy decisions when they are not in the majority.

Women are ‘strategic’ about running for office

Dittmar said cultural norms may also cause more women to refrain from seeking office.

“Women are strategic about where they run and when they run and why they run,” she said. “That it’s not going to hurt their family and they’re going to be able to win.”

As PBS NewsHour reported this month, those kinds of challenges can be seen in Utah, a state that has one of the fewest number of women in the nation on its state legislature and one whose culture is often influenced by the Mormon Church.

On the Utah State Legislature, six of 29 state senators and 10 of 75 representatives in the House are women, despite the fact that 60 percent of the state’s workforce are comprised of women.

Sophia DiCaro, a Republican incumbent to the Utah State House of Representatives, said there are a number of factors for the gender gap.

“We have a part-time legislature, it is full-time intensity for a 45-day period,” she told the NewsHour. “So your family situation has to be such that you’re able to accommodate that kind of schedule. You have to have the availability of time and you have to have the financial ability to make it work, you’re not paid very much as a legislator.”

While Dittmar said it’s difficult to prove a correlation, the lack of women in legislatures across the country may also be influencing policies like paid family leave, education and reproductive rights. Some studies suggest women legislators at the state and congressional levels “tend to be more likely than male legislators to prioritize issues important to women,” she said.

Despite the challenges for women, this year there is a slight uptick in participation. Dittmar said 44 states are holding races for state legislature. Of the approximately 11,800 nominees, 2,602 are women, up from 2,537 the last election cycle.

“A couple of states don’t run this year,” she said. “Even with fewer states we have more women candidates. So that’s promising to us.”

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