Yesterday’s primary elections saw big wins for women in politics, but in the U.S., government is still primarily a man’s world. Currently, American’s only female governors are Jennifer Granholm (D-Mich.), Linda Lingle (R-Hawaii), Beverly Perdue (D-N.C.), Jan Brewer (R-Ariz.), M. Jodi Rell (R-Conn.) and Christine Gregoire (D-Wash.).

However, 27 U.S. states have never had a female governor, and no woman has ever served as president, according to the Center for American Women and Politics (CAWP) at Rutgers University. The first female governor was Nellie Tayloe Ross (D-Wyo.), who became the state’s leader in 1925, according to CAWP.

Additionally, the House of Representatives only has 73 women in its 435 seats, and the Senate only has 17 women in its 100 seats. That means the U.S. has a lower percentage of women in its legislature than 69 other countries, including Iraq, Pakistan, Turkmenistan, Venezuela and Cuba, according to the Inter-Parliamentary Union (IPU). However, the U.S. does have a higher proportion of women in its government than North Korea, by 1 percent, according to IPU.

“Between 1789 and today, the best we've ever done is right now,” said Victoria A. Budson, the executive director of the Women and Public Policy Program at Harvard University’s Kennedy School of Government. “When one looks at us and sees that we're 70th in the world, what's important to see is that as other countries more effectively utilize their talent pool, the U.S. is dropping."

A high incumbency rate for elected officials in the U.S. helps perpetuate a gender imbalance, Budson said. In elections for open seats, when challengers run against another new candidate, women win elections at the same rate as men, Budson said.

But yesterday's primaries do indicate that the male dominance in U.S. politics may be shifting, Budson said.

"Hillary Clinton, bar none, is the most serious presidential candidate in the history of the United States who’s female. And Sarah Palin is the first time the Republican Party has nominated a woman for Executive office. So there's no doubt this is a sea-change in American Politics,” Budson told Life’s Little Mysteries. “However, gains of the past do not guarantee what the landscape of the future will look like.”

This article was provided by Life's Little Mysteries, a sister site to LiveScience.