Story highlights It might not be possible to implement Sanders plan

Many states are already having trouble funding higher education

(CNN) Free college for all may sound appealing, but it's not as simple as Bernie Sanders makes it out to be.

Paying for college isn't only a major burden for families. It's also very costly for states, who would have to pick up one-third of students' tuition at public colleges and universities under Sanders' plan.

This would hit states at a time when most are having trouble funding higher education as it is. They are shifting more of the responsibility to students -- hiking tuition and fees -- to free up revenue to pay for Medicaid and K-12 education.

"There's not a lot of extra money to spend on other programs," said Brian Sigritz, state fiscal studies director for the National Association of State Budget Officers. "Things still remain tight."

What's more, many governors and lawmakers aren't keen on expanding state-based programs, even with the promise of federal funding. Some may not want to be beholden to Washington D.C., while others may not agree with subsidizing students from higher-income families.

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