Democratic Reps. Carolyn Maloney (N.Y.) and Anna Eshoo (Calif.) might rest easier knowing they currently occupy some of the most “women-friendly” terrain in the country, according to new research from two political scientists.     

In their new book, “Women & Congressional Elections: A Century of Change,” Professors Barbara Palmer and Dennis Simon set out to determine whether demographics make certain congressional districts more or less likely to elect a woman.

Political strategists have long used demographics to predict a particular party’s chances of electoral success in a district, but little is known about the characteristics of districts where women have made their mark. That, says Palmer, was the impetus for what became an expansive research project. Palmer and Simon, along with a team of researchers, compiled election data on every House race from 1956 to 2010, calculating each district’s probability of electing a woman to office.    

“If you look at a congressional district, and you know the demographics, you can predict whether a Republican or a Democrat is going to win,” says Palmer, a political science professor at Baldwin Wallace College. “So we came up with this idea: Can you use those same demographics and predict whether a man or a woman will win?”     

Of the 72 women elected to the House in 2010, 33 were elected from California, New York and Florida. The proximity is no coincidence. In their research, Palmer and Simon found that women-friendly districts typically have high-income, educated electorates that are ethnically and racially diverse—characteristics found in a number of House districts in all three of those states.  

At the same time, families and blue collar workers—segments of society that typically harbor more socially conservative views—tend to be scarce in such districts.

“If you want to think of the Denver district Diana DeGette has or Nancy Pelosi’s [district], which is four-fifths of San Francisco, it’s at the same time high-end but diverse—slightly Bohemian, less of a business population and more entrepreneurial and creative,” says Simon, a political science professor at Southern Methodist University.

Other contributing factors, according to the research: smaller district size and an urban environment, which grant women more geographic mobility and typically lead to a larger pool of female candidates. While the latest round of redistricting has scrambled the make-up of some of the districts Palmer and Simon studied, the researchers expect the terrain they identified as "women-friendly" to remain favorable to female candidates.   

The 10 most women-friendly districts (2010 boundaries): NY-14, CA-8, NY-15, NY-8, MA-8, CA-30, CA-14, MD-8,CA-9, and CA-12.

And when it comes to redistricting, Palmer and Simon’s research reinforces the idea that female candidates often find themselves at a disadvantage. The recent re-draws in Georgia, North Carolina and New Jersey spurred complaints from female legislators.

“When politicians draw state districts, they’re thinking solely about themselves, and so it revolves around partisanship and incumbency,” says Simon. But, the researchers argue, as politicians redistrict, they’re also unintentionally “gender-mandering” while they’re gerrymandering. This can place a congresswoman in an unfavorable position from which to defend her seat, especially because female incumbents are more likely to be challenged in a primary election than their male counterparts.

“There’s a perception there that simply because they’re a woman, they’re electorally vulnerable,” says Simon. “Particularly, I would say, early in their career or if they had a close election last time.”