While discriminatory attitudes certainly play a role, they certainly don't explain why women do so much better in some nations than others. The key lies in the rules for how elections are conducted. Proportional representation systems use multi-seat districts where a political party or grouping of voters may need only 5 percent of the popular vote to win representation. Sweden, Finland, Norway and the Netherlands, the world's leaders in electing women, all use proportional representation. In fact, comparative research has shown that the leading predictor of women's success in national elections, when tested against all other variables, is use of proportional representation.
Women also are less likely to run when there is only one representative.
Electing more women to legislatures is not only a matter of fairness. Practically speaking, the presence of women in legislatures makes a measurable difference in the types of legislation that are proposed and passed into law. Implementation of proportional systems in the United States at local, state and national levels does not require revising the Constitution. Changes in applicable local, state and federal laws will do. It is high time to seriously address why 52 percent of the population only has 13 percent of the representation.