On June 4, California-based lesbian activist and Democratic Party leader Jean O’Leary died at the San Clemente home of Lisa Phelps, her partner of 12 years. She was 57.

“Jean was really the one out there plowing new territory,” longtime friend and POZ Magazine founder Sean Strub told The Associated Press. “At a time when a lot of the gay activist community couldn’t be ambitious enough to think about having a meeting at the White House, Jean was out there pulling the strings to make it happen,” he said. Strub announced O’Leary’s death in a press release issued on Sunday.

O’Leary had been battling lung cancer for the last two years. In a March 2 interview last year with The Advocate, O’Leary said she had been diagnosed with stage-four lung cancer in September 2003 and was given six to 18 months to live.

Over the course of her 35-year career, O’Leary ran several national GLBT rights groups and co-founded activist organizations such Lesbian Feminist Liberation, and co-founded National Coming Out Day in 1988 with Rob Eichbergis. The national observance is now a project of the Human Rights Campaign.

O’Leary was also active in Democratic politics, working extensively to elect candidates. In 1976, she was one of three openly gay delegates sent to the Democratic National Convention. She chaired the Democratic National Committee’s Gay and Lesbian Caucus from 1992 to 2002.

Originally born in Kingston, N.Y., O’Leary grew up mostly in Ohio. At her high school graduation speech in 1966, she announced her entry into the Sisters of the Holy Humility convent. She said in a 1984 book, Lesbian Nuns: Breaking Silence, that she wanted to become a nun because she “wanted to do something special” due to an absence of women’s, gay and anti-war movements in Ohio at the time. It was during her four-year stay in the convent where she came to terms with her sexuality.

O’Leary attended Cleveland State University while at the convent and graduated with a degree in psychology in 1970. She left the convent and moved to New York City to pursue a doctorate in organizational development at Yeshiva University the following year.

During her time at Yeshiva, O’Leary joined the Gay Activists Alliance (GAA), a primarily male-dominated organization led by Bruce Voeller. Differences of opinion led her and other women to leave GAA to form the Lesbian Feminist Liberation.

“Jean O’Leary was a link of kindness and humanity and inclusive politics, who helped the women’s movement to recognize the universal cost of homophobia, and the gay movement to see that marginalizing the voices of lesbians would only diminish its power,” feminist leader Gloria Steinem said in a statement.

Years later, O’Leary joined forces with Voeller and became co-executive director of the National Gay Task Force, now the National Gay and Lesbian Task Force (NGLTF). She served in that position from 1976 to 1979.

“[O’Leary] advocated for gay rights in immigration and naturalization law, campaigned to repeal anti-sodomy statues, and advocated with the Federal Communications Commission and the U.S. Civil Rights Commission,” said NGLTF Executive Director Matt Foreman. “In all, her efforts helped make gay rights a national issue in the late 1970s. Her commitments to feminism and anti-racism live on as core values of the Task Force.”

O’Leary organized the first-ever White House meeting with gay and lesbian rights advocates in March 1977 through the help of longtime friend Midge Costanza, now a San Diego activist who was then a special assistant to President Jimmy Carter. O’Leary was also the first openly gay person appointed to a presidential commission, during President Carter’s term.

“I will always remember Jean’s first call to me at the White House, requesting a meeting with the president,” Costanza said in Strub’s press release. “With the courage and tenacity so typical of Jean, she demanded that I hold a meeting in the White House to discuss federal government policies that specifically discriminated against gays and lesbians. Because of this historic gathering of gay and lesbian leaders in the White House, a national discussion was held to review and begin to correct the anti-gay policies by federal government agencies. Many changes were made, and many doors were opened as a result of Jean’s perseverance.”

In addition to her partner, O’Leary is survived by two brothers, a sister, and Phelps’ two children.

“I am proud to have been with Jean during the last 12 years of her life, and I am proud of Jean’s political accomplishments,” Phelps said. “She set an example of community involvement for our 15-year-old daughter, Victoria, and instilled in her the importance of political activism.”

A memorial service is being planned at the Los Angeles Gay and Lesbian Community Services Center.