Cokie Roberts, correspondent for National Public Radio and ABC News, draws some fascinating political lessons for women in her book, "We Are Our Mothers' Daughters." For decades, she says, women worked unceasingly for the right to vote, but when they finally won their battle in 1920, many women did not vote. Thus, their political, economic and social opportunities languished.

She cites discriminatory legislation that Congress passed even after women earned the right to vote. Depression-era laws, for example, specified that the wives of federal employees could not hold government jobs and that wives of employed men had to be fired first when lay-offs occurred. The 1935 National Recovery Act mandated that women in government employment be paid 25 percent less than men in the same job. Not until1963 was this blatant discrimination overturned. And, not until the 1964 Civil Rights Act did job discrimination based on gender become illegal.

In 1963, many states still gave husbands complete control over their wives' earnings. Some states prohibited inheritance by women and even barred women from going into business by themselves.

Then, in 1972, major pieces of anti-discriminatory legislation passed Congress. Title IX banned discrimination in education, including sports, creating, as Roberts writes, "a whole generation of women athletes." She goes on, "Then came equal credit, creating a whole generation of women business owners."

What had changed? Why, so many years after suffrage, were women finally getting equal treatment under the law? In the 1970's, women started getting elected to state legislatures and Congress. Despite tiny numbers, they began to push women's issues. Women began talking to their elected female representatives as they had never talked to their male representatives. They talked to them about their concerns over inadequate child care and health care. Since a generation of women had begun moving into the work force, they also talked about Social Security and unequal pay.

Then, in 1982, women began voting in larger numbers than men for the first time. And they began, also for the first time, to vote differently from men. The gender gap, says Roberts, was not women voting for women, but women voting for their economic interests. What grabbed politicians' attention in 1982 is that the women's vote elected politicians who had lost the men's vote. If women hadn't voted in 1982, Governors Mario Cuomo of New York and James Blanchard of Michigan and 26 members of Congress wouldn't have been elected.

The1992 election was the first time you could really see the gender gap, when more women than ever were elected to Congress. These women, pushed by female voters who feared for their children's safety, ensured that the assault weapons ban passed in 1993. By 1996, the Republican Congress was really paying attention. It passed an increase in the minimum wage, of great interest to women, who make up two-thirds of minimum wage earners. It also stopped "drive by" deliveries and added domestic violence to the list of crimes that kept people from getting guns.

The lessons Cokie Roberts draws from all this are clear. When women vote and vote differently from men, they elect both women and men who will push for their interests. Second, as Ms. Roberts puts it, women come "to the table of government with different sensibilities. Women simply experience life differently from men." They bring, she adds, their perspectives as mothers, sisters, daughters and wives to the role of governing. Finally, if women continue to vote in large numbers and for their interests, they will continue to change the agenda and the composition of governing bodies. The women's vote does indeed make a big difference.