Ruth Shack, who as a freshman commissioner in Dade County, Fla., in 1977 championed one of America’s first local ordinances protecting gays and lesbians from discrimination, only to see it overturned after a high-profile campaign by the conservative activist Anita Bryant, died on May 23 in Cumming, Ga. She was 94.

Her daughter Barbara Shack said the death, in a hospital, was from a brief respiratory illness. Ms. Shack had moved to Cumming during the pandemic to be close to her family.

Dade County, home to Miami, is a bustling global metropolis with a vibrant gay community. It looked very different in 1976, when Ms. Shack was elected to a two-year term on the county commission. It was seven years after the Stonewall Uprising in New York set off the modern gay rights movement, but in places like Miami, homosexuality still carried a stigma.

A liberal Democrat, Ms. Shack had run with the support of a coalition of gay-rights activists. Weeks after she won, she introduced an amendment to add “sexual preference” to the list of characteristics protected against discrimination in housing, education and the workplace.

“People forget that back in 1977, gay people could be fired, could be jailed, could be sent out of their homes and out of theaters,” she told Tablet magazine in 2016. “To see my friends going to jail just for being in the wrong place at the wrong time was horrific.”

The commission approved the amendment by a 5-3 vote, but opposition was growing rapidly.

In a strange coincidence, it was led by one of her talent-agent husband’s best-known clients, Ms. Bryant, a singer, former beauty pageant contestant and spokeswoman for Florida orange juice who had become involved in conservative Christian causes.

Soon after the vote, Ms. Bryant, who had often socialized with the Shacks, called Ms. Shack at home.

“I am going to have to oppose you,” Ms. Bryant said, according to “Rebels, Rubyfruit, and Rhinestones: Queering Space in the Stonewall South” (2001) by James T. Sears. Then she began to read from the Bible.

“I grew up during the Holocaust,” Ms. Shack, who was Jewish, responded. “I see this as a human rights issue.”

Ms. Bryant said she disagreed and hung up.

Over the next several months, Ms. Bryant gained a national following with her campaign to overturn the law, drawing donations from around the country for an anti-gay coalition that she founded and called Save Our Children. Ms. Shack, for her part, received death threats and denunciations from religious leaders.

In a referendum in June 1977, 69 percent of Dade County voters favored overturning the law. Many observers said it was the end of Ms. Shack’s political career, but she handily won re-election in 1978 and remained in office until 1986. During that time, she championed other causes, including the county’s first historic-preservation law.

She also led the effort to approve an audacious project by the French husband-and-wife artists Christo and Jeanne-Claude to wrap 11 islands in Biscayne Bay in pink fabric. The 1983 project, “Surrounded Islands,” became an international sensation and helped establish the city as a major arts center.

Ruth Naomi Burrows was born on Aug. 24, 1931, in Brooklyn and raised in Bay Shore, on the South Shore of Long Island. Her mother, Roslyn (Zimmerman) Burrows, was an interior designer who helped her father, James Burrows, run his wallpaper and art-supply store.

The store was a popular pit stop for artists on their way to the East End of Long Island; Jackson Pollock was a regular customer.

Growing up in the store instilled a lifelong love of art in Ms. Shack, while growing up in a liberal family instilled a lifelong love of politics. “Other people wanted to be Shirley Temple,” she told The Miami Herald in 1984. “I wanted to be Franklin Delano Roosevelt.”

She spent two years at Mary Washington College of the University of Virginia (now the University of Mary Washington in Fredericksburg) before dropping out, telling her father that college was a “poor investment.” Returning to New York City, she designed storefront displays and campaigned for the 1952 Democratic presidential nominee Adlai E. Stevenson.

Ms. Shack received a bachelor’s degree in English from Barry College (now University) in Miami in 1970 and a master’s degree in social science from the University of Colorado in 1975.

She met Richard Shack on a blind date, and they married in 1953. After the wedding, they hopped into his red Hudson convertible and drove to Miami Beach for a two-week honeymoon.

They fell in love with the city and decided to stay, despite concerns about overt prejudice. They faced antisemitism, and Black visitors in Miami Beach, including those Mr. Shack represented, had to leave town at sundown or risk arrest.

But it was also a rapidly growing place, and Ms. Shack embraced opportunities to change it. While raising their three daughters, she became active in local Jewish organizations, civil rights activities and the women’s movement.

Mr. Shack died in 2012. Along with their daughter Barbara, Ms. Shack is survived by two other daughters, Janice Shack-Marquez and Lynda Streitenberger; five grandchildren; and four great-grandchildren.

After leaving the Dade County Commission in 1986, Ms. Shack became president of the Dade Community Foundation (now the Miami Foundation), an arts and cultural organization that in her hands grew into one of the largest in Florida. She retired in 2009.

In 1998, the county commission passed a new anti-discrimination ordinance almost identical to the one Ms. Shack had sponsored more than two decades earlier. This time, the city’s political and cultural leadership turned out en masse to support it — a sign, Ms. Shack liked to say, of how much Miami had changed.

“Life here was and is so remarkably exciting and wonderful, and it changes every hour on the hour,” she told Outwords magazine in 2018. “I tell people, ‘If you don’t like change, get out. You’re going to hate it here, because it won’t be the same next week.’”