>> PHOTOS: Notable supporters of 2016 presidential candidates
The average price of in-state tuition at four-year colleges ranged from just under $5,000 in Wyoming to over $15,000 in New Hampshire for the 2015-2016 school year.
Clinton's team estimates the plan would cost about $350 billion over the next 10 years but says it would be paid for by limiting tax expenditures for high-income taxpayers.
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Clinton's proposal was inspired by, but isn't identical to, the one touted by Sanders. That plan would help more students but cost $75 billion every year.
This video includes clips from the University of Wyoming and C-SPAN. Music provided courtesy of APM Music.