She based the approach on what was then a newly minted concept in political circles: the existence of a gender gap in voting patterns. Ms. Lynch and others, analyzing exit polls from the 1980 and 1982 national elections, had discerned a wide disparity between male and female voters on fundamental issues like war and peace, help for the needy and economic growth: Women, who tended to be more peaceable, more amenable to government help for the needy, and more likely to favor bottom-up rather than top-down strategies for economic growth, were more likely to vote Democratic and could not necessarily be expected to vote the way their husbands did, as old-school political operatives had always thought.

To capitalize on the gap, Ms. Lynch encouraged Mr. Hart to campaign in settings where there were lots of women, to prominently feature women in his television commercials, and to pay homage in his speeches to the economic and political power of women. (Mr. Hart’s campaign for the 1988 nomination collapsed after he was photographed with a woman in a bathing suit on his lap.)

By the time Ms. Lynch was overshadowed by another pollster, Patrick Caddell, the architect of Jimmy Carter’s out-of-nowhere 1976 campaign, Mr. Hart had become a front-runner. Ms. Lynch and Mr. Caddell clashed, and he soon pushed her “women’s strategy” aside as too narrow in its focus.

Geoffrey Garin, president of Hart Research Associates, a political consulting firm in Washington, said in an interview on Monday that Ms. Lynch was nonetheless the more prescient in her strategy. “The things she noticed about gender and American politics became the common wisdom very quickly,” he said.

Dorothea Jean Lynch was born in Brooklyn on July 24, 1945, to Mortimer Lynch and the former Dorothea Reeves. Her father was a pressman for The New York Times. “I thought growing up an Irish Catholic Democrat in Brooklyn in the 1950s was about the best thing anyone could be, and I treasured each one of those labels,” she wrote in an essay for “American Catholics and Civic Engagement: A Distinctive Voice,” a collection of essays published in 2003.