What changes when there are more women in government? Probably a lot more than you think.

Yes, a woman hasn't yet been elected president. But in 2017, there are a record 21 women serving in the US Senate, with 83 more in the House of Representatives. Women make up nearly 25 percent of state legislators, according to Rutgers' Eagleton Institute of Politics.

Women's representation in politics is growing slowly, but it's growing. And as more and more women start to occupy all levels of government, we should expect them to govern differently.

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Political science research has found this over and over again: Women legislators are more likely to introduce legislation that specifically benefits women. They’re better at bringing funding back to their home districts. And, to put it bluntly, they just get more shit done: A woman legislator, on average, passed twice as many bills as a male legislator in one recent session of Congress.

Women bring a different background to Congress. They face different obstacles to success — and sometimes more obstacles to winning office. That shapes how they govern and what issues they choose to focus their time on.

There is, obviously, no research on women presidents in the United States. But political scientists think their findings about Congress would apply to a woman president as well because of the shared experience and obstacles that all women politicians face.

Women legislators sponsor more bills, pass more laws, and send their districts more money

Congress has become increasingly female over the past three decades. In 1991 there were 33 women legislators. Today there are 104. While that’s far from gender parity — men still outnumber women four to one in Congress — it is already true that having more women in Congress has changed the way the legislative body works.

Michele Swers, a political scientist at Georgetown University, has written multiple books examining how this shifting gender balance has changed the body. Her research consistently finds that women in Congress tend to shift the conversation to focus more on bills and policies that relate to women specifically — such as increasing paid leave or prosecuting violence against women.

One of her papers looked at Congress in the mid-1990s, comparing male and female legislators of similar ideologies. She found that liberal female legislators co-sponsored an average of 10.6 bills related to women’s health — an average of 5.3 more than their liberal male colleagues.

Women in Congress pass, on average, twice as many bills as their male colleagues

Changing the conversation can have an effect on the laws that Congress eventually passes: One recent study of Congress since 2009 found that the average female legislator had 2.31 of her bills enacted, compared with men, who turned 1.57 bills into law.

"Women in Congress are just more likely to prioritize issues that have a direct connection to women — violence against women, family leave policy, those kind of things," Swers says. "The more you can directly connect the consequence to women, the more you see female legislators getting involved."

The "Jill Robinson theory" of high-achieving, women Congress members

Another way legislators serve their constituents is by bringing programs and money to their districts — securing more money to start a pre-K program, for example, or dollars to repave local roads.

All told, Congress allocated $20.8 trillion in federal outlays (excluding defense and military spending) from 1984 to 2004. Women, it turns out, did a better job at getting their share of that money. On average, female legislators sent 9 percent more funds back to their districts than their male colleagues. Districts represented by women received an additional $49 million annually on average compared to their male-represented counterparts.

Sarah Anzia, the author of this study, argues that this might reflect something particular about the type of women who run for Congress. Multiple studies have found that women underestimate their qualifications for office compared to men. When you look at a comparable group of lawyers, business leaders, and others likely to run for office, the men are significantly more likely to say that they’d make a good politician.

"One of the common jokes in this field is that every day, there are a million men who wake up in the morning, look in the mirror, and say 'I’d be a great congressman,'" says Heidi Hartmann, an economist who runs the Institute for Women’s Policy Research. "And there aren’t that many women who do that."

As such, Anzia hypothesizes that the women who do assess their qualifications positively are those who are actually overqualified for the job.

"If women … underestimate their qualifications for office, then only the most qualified, politically ambitious females will emerge as candidates," Anzia writes. "The women who are elected to office will perform better, on average, than their male counterparts."

Anzia dubs this the "Jill Robinson effect" after Jackie Robinson, the first black baseball player who was also heralded as one of the top talents in the game. "Robinson had to be better than almost any white player in order to overcome the prejudice of owners, players, and fans," Anzia writes.

Women still face hurdles to running for office

Women politicians don’t face the same hurdles as Robinson did — but there are still obstacles that impede women’s ability to pursue office. Gender norms, for example, shape the responsibilities that women have outside the office. Potential women candidates are 15 times more likely to be responsible for the child care in their homes — and six times more likely to shoulder the majority of housework.

Women are also much less likely to have others encourage them to run for office — whether that’s a party official or even a friend in passing conversation.

With these obstacles — and with the 2016 campaign still a vivid memory — it can be hard to imagine when a woman will next decide to run for president, or when one will be able to win.

Maybe the woman who finally is elected to the presidency won't fit the patterns that researchers have found among woman legislators. It is true that women politicians running for any position do bring their own perspective into office. That could shape the type of policies one might pursue in the White House or Congress. At the same time, presidents are subject to significantly more competing interests than members of Congress — and have a much larger staff shaping their policy agenda. That could make a woman president look less like a woman Congress member.

But what we know, at this point, about elected female officials is this: Their experience shapes how they govern. And the success of women who do serve in Congress can reflect not just their skill as legislators but also their skill to get there in the first place.

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