While Democrats narrow in on a spending package — President Biden this week suggested a range of $1.9 to $2.2 trillion, significantly lower than his initial $3.5 trillion plan — Senator Elizabeth Warren called into Boston Public Radio to make her case for robust child care measures.

Warren said part of the package would federally subsidize higher wages for every child care and preschool worker in America.

"This is a field where the turnover is 30% a year... they make more money if they go work the cash register of McDonald's. So part of what we're trying to do is build up supply for everybody," she said.

Warren has been pushing to cap the amount some families pay for child care at no more than 7 percent of their income, up to incomes of $150,000.

According to a New York Times article, the United States government spends on average around $500 a year per child, significantly lower than the tens of thousands of dollars other wealthy nations like Finland and Germany spend per child. And even though an expanded child tax credit has been immediately helpful for some American families, it remains a temporary provision.

In Massachusetts, child care costs are among the highest in the nation.

During a call-in segment on the show, one caller said his family was moving to England — where his wife is from — partly because of the free child care there. Others recounted astronomical costs for preschool, some as much as a college tuition.

Warren said Congress has used infrastructure packages "for more than half a century" to raise wages of construction workers who build highways and bridges, and it's now time to extend that infrastructure to social services.

"The reason the pay is so low [for child care workers] is it's literally all that families can afford," she said.

Warren said she is still pushing for certain provisions in her plan — a holdover from her 2020 presidential bid — to be included in the final bill, which currently calls for a cap on child care costs at 7 percent of their income for some households.

"The actual minimum is probably 150% of state medium income," she said of the income cutoff in the current iteration of the plan. "And that is the top, meaning if you're a dollar above that, you get nothing. But leading up to that, the lower your income is, you get it for free. Then you kinda get on a slope where you have to pay one percent of your income, two percent of your income, three percent of your income first, up to a maximum of 7%."

Warren then said she wants to remove the income qualifier, and "just say as long as you're paying 7% up front, no family has to pay more than 7% to a child care center."