Democratic presidential candidate Senator Bernie Sanders speaks at a breakfast campaign stop one day before the New Hampshire presidential primary election in Manchester, New Hampshire, February 10, 2020.

Sen. Bernie Sanders unveiled a plan Monday to provide universal child care and pre-K, the broadest proposal yet from the 2020 Democratic presidential field to address a key issue for the party.

The Vermont senator wants to put $1.5 trillion over a decade into guaranteed child care through age 3 followed by free pre-kindergarten education. The Sanders campaign says the programs would not only help childhood development but also combat income inequality, improve job flexibility for parents and boost wages and training for child-care workers.

"As president, we will guarantee free, universal childcare and pre-kindergarten to every child in America to help level the playing field, create new and good jobs, and enable parents to more easily balance the demands of work and home," Sanders said in a statement.

The senator, the national delegate leader in the Democratic race after a projected win in Saturday's Nevada caucus, appears to go further on the issue than his chief rivals for the nomination. Under the plan, the U.S. government would fund universal free child care. State and tribal governments would administer the program with federal quality standards such as minimum wages for workers.

The U.S. government would also fund free full-day pre-K, which would be run locally.

Sanders would pay for the programs through his "tax on extreme wealth" over $32 million. His campaign has said the tax would raise about $4.35 trillion over 10 years.

Some of Sanders' top rivals for the Democratic nomination have released their own child-care plans, but his proposal seems to have a broader scope.

Sen. Elizabeth Warren, D-Mass., put forward a measure to slash child-care costs and make the services free for families that earn up to 200% of the federal poverty level. Her campaign said the proposal would cost an estimated $700 billion over 10 years.

Former South Bend Mayor Pete Buttigieg has also called to invest $700 billion over a decade to make child care more affordable. Former New York Mayor Mike Bloomberg and Sen. Amy Klobuchar, D-Minn., have also outlined programs to reduce costs for child care.

Former Vice President Joe Biden and billionaire activist Tom Steyer have previously indicated support for free universal pre-K. Buttigieg, Warren and Klobuchar have backed making it free for low-income families.

Sanders, who has run a populist political "revolution," has emerged as the primary's front-runner early in the nominating contests. Monday's proposal fits into an array of Sanders plans meant to boost workers and low-income Americans: He wants to implement a single-payer "Medicare for All" system, cancel student debt and make public college free, boost the minimum wage to $15 per hour and strengthen labor rights.

The senator's new plan calls for the construction or renovation of facilities to meet the demands of expanded child care. It also pushes for protections for children with disabilities within the structure of the federally funded services.

As part of the proposal, Sanders also urged passage of a separate piece of legislation, the Universal School Meals Act, which he introduced along with Rep. Ilhan Omar, D-Minn. It would provide free breakfast, lunch and dinner to all students, regardless of income level.

Sanders also called for the implementation of his Thurgood Marshall plan, which would reduce preschool class sizes, increase English as a second language instruction, desegregate the public education system and put $50 billion into after-school and summer programs.

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