Low- and middle-income students would pay nothing for tuition at in-state public colleges under a new part of her college affordability plan unveiled Wednesday.

Any student whose family earns $85,000 or less would be eligible at first. The income level would go up by $10,000 each year until 2021, when anyone whose family makes $125,000 a year or less would go tuition-free.

That would cover more than 80% of all families, the Clinton campaign said.

The rich would still have to pay, unlike a plan proposed by Bernie Sanders, which would cover everyone. As Clinton has previously said, she doesnt want to pay for Donald Trumps children to go to college.

Tuition at state schools is already much cheaper than what private colleges charge. Last year, the average tuition for in-state students at public colleges was $9,410, according to The College Board. At private colleges, it was $32,410.

Still, about 66% of students earning a bachelors degree at public colleges in 2012 took out student loans, according to The College Board.

But tuition isnt everything when it comes to paying for college. Even with a tuition-free plan in place, students would still have to pay for room and board. On average, public colleges charged $10,140 for room and board last year. Thats even more than the average state school charged for tuition.

Some of the top private schools in the US already make tuition free for low- and middle-income students. At Princeton, students from families making less than $120,000 a year dont pay anything for tuition and receive grant money that covers at least some of their room and board. Stanford covers tuition for those making less than $125,000 a year.

The new policy proposal expands Clintons original affordability plan, which said that students would never have to borrow money in order to pay for tuition at public colleges. It would have likely estimated what a family could afford to pay based on their income, and offer grants and scholarships so they wouldnt have to pay more than that amount.

To foot the bill for the expanded plan, Clinton proposes closing additional high-income tax loopholes -- focusing on loopholes available especially to Wall Street money managers, like hedge funds and private equity firms, an aide said.