Democratic presidential candidate Kamala Harris on Tuesday announced details of her plan to boost salaries for teachers across the country.

The junior senator from California talked about the plan over the weekend at a campaign event in Houston, saying it would represent “the largest federal investment in teachers’ salaries in the history of the United States.”

The plan is one of the early key policy priorities of her 2020 run for the White House.

“I am declaring to you that by the end of my first term, we will have improved teacher salaries so that we close the pay gap, because right now teachers are making over 10 percent less than other college-educated graduates,” Harris said during the campaign event Saturday at Texas Southern University.

Ahead of the formal release, a campaign aide said the plan would raise average teacher pay by $13,500. Under Harris’ proposal, the federal government would be responsible for getting the ball rolling with the first 10 percent of the funding needed.

States would then be able to access federal matching funds that would provide $3 in federal support for every $1 of new state money, up to the point that the estimated gap with other college-educated workers closes.

“The federal government will make an additional targeted investment beyond just closing the gap to pay teachers in America’s highest-need schools more than other comparable professionals in their state. Students and teachers of color disproportionately learn and work in these schools,” a Harris aide said in a statement.

Arne Duncan, who served as secretary of Education in the Obama administration, was among the first to offer support for the early outline of the proposal.

“Radical idea: pay the professionals we entrust to teach, nurture and mentor our children a better salary!” Duncan tweeted on Saturday.

Randi Weingarten, the president of the American Federation of Teachers, was also among those offering advance praise for Harris.

“For every teacher in America and for the 91 percent of kids who attend our public schools, this is one of the most thoughtful initiatives we’ve seen in years. Sen. Harris is making sure that if we say teachers and education are important, we actually treat them that way,” Weingarten said in a statement. “While Donald Trump and Betsy DeVos have slashed programs and pushed a federal budget that makes the situation worse, Sen. Harris has crafted a concrete commitment to make things better.”

“Sen. Harris’ intervention spells out the clear choice faced by all 2020 candidates: whether to invest new resources, or revert to the failed top-down, test-and-punish mentality of decades past,” she added.

Teachers’ unions have traditionally formed a key Democratic constituency.

The Harris campaign predicted that the federal portion of the plan would cost an estimated $315 billion over the next decade, and it could be paid for with changes to the estate tax that would boost revenue.

“You can judge a society by the way it treats its children, and one of the greatest expressions of love that a society can give to its children is educating those children with the resources they need,” Harris said Saturday. “And teachers are our greatest resource in that endeavor.”

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