Elizabeth Warren’s plan for providing child care to all U.S. families who want it would require the creation of a massive, highly qualified workforce for an occupation that already struggles to attract workers.

Advocates for universal child care aren’t sure precisely how many workers would be needed for the endeavor, but they know the U.S. already is facing a drastic worker shortage. One analysis,from the left-leaning Center for American Progress, found that half of families live in places with no available child care.

“As much as I’m supportive of improving our child care in this country, there are some very deep-seated issues that will take a lot of public will and money to take us where we need to be,” said Kristin Schubert, a child health expert at the Robert Wood Johnson Foundation.

Warren’s plan, released earlier this week as one of the Massachusetts senator’s first presidential campaign proposals, would provide fully government-funded child care to families that fall below a certain income threshold. Families of four who make roughly $51,500 a year would receive child care at no cost to them. The rest would pay no more than 7 percent of their income on child care, with the federal government picking up the remainder of the tab.

The proposal, the Universal Child Care and Early Learning Act, would entail a significant shift of resources toward child care relative to the status quo, in which two-parent households spend more than 10 percent of of their incomes on child care while single parents spend closer to 36 percent, according to the advocacy group Child Care Aware of America. Roughly 2.6 million children receive some type of government subsidy that helps cover child care.

Warren’s proposal, known as the Universal Child Care and Early Learning Act, would significantly expand child care programs when there aren’t enough skilled child care workers to adequately support the 6.8 million infants and toddlers in daycare now. Moody’s Analytics estimated that her plan would allow 12 million more children to have access to daycare. Meeting that demand would require recruiting more workers and re-training those already in the field, largely because Warren’s plan requires daycares to meet rigorous standards.

Even if, as proponents contend, federal spending and dedication could overcome those obstacles, the plan would still face major logistical hurdles. For example, the government would have to figure out how to accommodate families with extra needs, such as requiring daycare overnight because they don’t work 9-to-5 jobs, or needing care close to remote areas where they work or live.

Both rural areas and cities face a daycare worker shortage. Washington, D.C., for instance, has only about one child care slot for every three infants and toddlers who live in the city. As a result, parents often rush to get on daycare waiting lists when they first learn they are pregnant.

The Bureau of Labor Statistics estimates that as many as 1.2 million people work in registered or licensed child care, a number that includes teaching assistants and preschool teachers. The exact number of how many more child care workers would be needed to realize Warren’s vision is hard to pin down, in part because there aren’t good data about unregulated daycares.

A previous analysis of a similar Senate bill, the Childcare for Working Families Act introduced by Sen. Patty Murray, D-Wash., offers some insight. The Center for American Progress estimated that the measure would create 700,000 child care jobs, but it isn’t clear whether that figure would be adequate in meeting child care demand.

“Any of these proposals would have to have a real ramp-up process to get the workforce in place to do it,” said Patricia Cole, senior director of federal policy for Zero to Three, a group that advocates for policies supporting parents, infants, and toddlers. “It certainly wouldn’t happen overnight.”

Several parts of a universal child care plan would have to fall into place at the same time, advocates say. The federal government would have to pay for recruiting new staff and training current employees to meet new child care standards. And they’d have to tempt them with higher pay: If people have to meet higher standards without higher wages, they are likely to seek other work.

“Right now, the state of play is: It’s bad,” said Schubert of the Robert Wood Johnson Foundation. “It’s really bad in terms of what we pay this workforce. A lot of [child care workers] are working way under livable wage.”

Daycare workers are paid about $10.72 per hour, according to the Bureau of Labor Statistics, and the job often doesn’t come with health or retirement benefits, causing workers to rely on public programs. The sector has a turnover rate of approximately 25 percent. Child care workers with college educations tend to move on to better-paying early education jobs.

“It becomes very difficult to recruit and retrain qualified teachers at that salary level,” said Katie Hamm, vice president of early childhood policy at the Center for American Progress.

Warren’s office did not respond to inquiries, but her plan does propose that the government pay for worker training and professional development. It also proposes that child care workers make salaries similar to those of public school teachers.

All of the provisions, including child care subsidies, would be funded through Warren’s proposed wealth tax, or what she calls the “Ultra-Millionaire Tax.” The tax would start at a 2 percent rate for households with net worths above $50 million and rise to 3 percent for billionaire households.

Warren’s team cited an analysis by Moody’s Analytics to conclude that her child care plan would cost the Treasury $70 billion a year — about as much as was spent last year by the Department of Homeland Security.

Another study from 2018, from the National Academies of Sciences, Engineering, and Medicine concluded that making education from birth to kindergarten more accessible, affordable, and higher quality would require $82 billion a year in public spending and $58 billion in private spending, for a total of $140 billion a year.

The projections for both of these call for training and certification of current staff. Under Warren’s plan, daycares that don’t meet meet standards similar to the U.S. military child care and Head Start programs wouldn’t get federal funding.

Getting there would require rationalizing existing regulations because states differ in requirements for licensing child care facilities. Generally, unlicensed daycares haven’t had regular inspections to check for fire safety or don’t require a criminal background check for staff. Licensing standards require a certain child-to-caregiver ratio, as well as specific training in CPR or First Aid.

Child care advocates think that the standards for child care workers should extend to educational training, because vast brain development occurs among infants and toddlers.

“This is not just babysitting,” said Schubert.

Advocates of those standards believes that achieving them would require child care workers to have advanced degrees — and the time to work toward them.

“The only way to professionalize a workforce and raise the compensation is to have some kind of indication that people have gotten the training and education,” Cole said.

She added that such an endeavor would require significant funding and time but stressed that training and credentialing child care workers may not need to be laser-focused on a specific degree or program to produce high-quality workers.

Hamm agreed, noting that people already in the field had valuable experience.

“There has to be a balanced support that helps child care workers get the skills they need but doesn’t penalize people who are further in their careers and have lived experiences that contribute to their knowledge base,” she said.