SACRAMENTO — California is about to wade back into the fight over affirmative action, nearly a quarter-century after state voters banned the consideration of race and sex in public education, employment and contracting.

Lawmakers and civil rights groups said Tuesday they would try to repeal Proposition 209, the 1996 state constitutional amendment that they argue has been devastating for women and people of color.

They will ask the Legislature to put ACA5 on the November ballot. It would strip language from the state Constitution prohibiting universities, schools and government agencies from using race or sex in their admissions criteria, hiring and procurement decisions.

It must pass both the Assembly and the Senate with a two-thirds vote by the end of June to qualify for the ballot. Voters could then repeal Prop. 209 by a simple majority.

Debate over Prop. 209, both in the years leading up to it and the decades since, focused largely on race-conscious policies in college admissions. But supporters of repealing the affirmative action ban said it has had broader impacts that have received far less attention, including curtailing efforts to use hiring to increase diversity in police departments and school workforces.

The campaign will largely focus on public contracting, where critics said changes resulting from Prop. 209 cost small businesses run by women and people of color billions of dollars.

“We have all survived and endured Proposition 209, and it has not been a luxury,” said Assemblywoman Shirley Weber, the San Diego Democrat who is carrying the measure. “It has been a hard journey. And it has caused a lot of losses.”

Prop. 209 was the culmination of decades of controversy over affirmative action policies in California. It was championed by then-Gov. Pete Wilson, who used the issue to help launch an unsuccessful bid for president, and other Republican politicians, including eventual 1996 presidential nominee Bob Dole.

After the measure passed with nearly 55% of the vote, Wilson hailed a new era of equal opportunity under the law, where Californians would be judged only by their merit.

But the change has remained divisive. Opponents point to examples like UC Berkeley, one of the most selective universities in the state, where the proportion of Latino and black freshmen dropped by half immediately after Prop. 209 took effect. Despite gains, those students continue to be underrepresented compared to California as a whole.

Eva Paterson, a civil rights attorney and president of the nonprofit Equal Justice Society in Oakland, was a self-proclaimed “affirmative action admittee” to Berkeley Law School in 1972. She said she has been looking for a way to undo Prop. 209 ever since it passed.

With opposition to President Trump expected to drive a motivated liberal electorate this November, she said, the time is right to mount a challenge.

“Trump and his white supremacist friends have shown very clearly that racism and discrimination is very much alive and well,” Paterson said. “You’ve got this perfect storm of a change.”

The Legislature last considered the issue in 2014, when a proposed constitutional amendment that would have asked voters to reverse the ban on consideration of race and sex in college admissions passed the Senate before being caught up in complex racial politics.

Concerned that it would limit their children’s ability to get into California’s most selective colleges, Asian American groups mobilized against the measure. Their campaign included town hall meetings across the state and a drive to re-register Asian American Democrats as Republicans. That led three Asian American state senators who had already voted for the proposal to ask legislative leaders to hold it.

Representatives for one of the groups, the 80-20 National Asian American Political Action Committee, did not immediately respond to a request for comment Tuesday. But the organization has fought in court to overturn college affirmative action policies that it says discriminate against Asian American applicants by holding them to a higher academic standard.

Paterson said she is sympathetic to fears that repealing Prop. 209 would shut students out of elite colleges. But she said Asian Americans have also been hurt by the law, particularly in public contracting.

Her group commissioned a study in 2015 that concluded businesses owned by women and people of color have lost out on more than $1 billion annually in state and local government contracts since the elimination of affirmative action programs. Procurement with those businesses by Caltrans, for example, had dropped by more than three-quarters.

“We pay taxes. Those are our tax dollars and we’re not getting any of that money,” Paterson said. “This is a way of leveling the playing field and getting money to qualified people of color.”

Anne Cervantes, an architect in San Francisco, said she has struggled her whole career with a “glass ceiling” in her industry for women and Latinos. Without race-conscious programs, she said, it’s hard for her firm to compete against bigger companies with more connections.

“How is a small office like mine, under 10, going to participate or even grow?” she said. Repealing Prop. 209, she said, “would open the floodgates for everyone to participate.”

Alexei Koseff is a San Francisco Chronicle staff writer. Email: alexei.koseff@sfchronicle.com Twitter: @akoseff