Young people rallied to Sen. Bernie Sanders’s presidential campaign in 2016, amid his calls for public colleges and universities to be free.

Sanders won a landslide 86% of votes from Iowa caucus-goers ages 17 to 24 — according to CNN entrance polls — but in the 2020 primary there are several candidates calling for the tuition policies Sanders brought to the forefront, and some plans go beyond what he proposed then.

Sen. Elizabeth Warren debuted her own education plan in April — making all public technical schools and two and four-year colleges tuition free.

Warren’s proposal would also wipe away up to $50,000 in student debt for people with a household income up to $100,000, and diminishing debt relief for all income beyond $100,000 up to $250,000.

Sanders subsequently called for the writing-off of all $1.6 trillion in student loan debt held by Americans in a June proposal, regardless of household income.

Respectively, Sanders and Warren have the support of 24% and 19% of likely Democratic primary voters ages 18 to 29, according to the latest YouGov poll. The only other candidate to receive double digit support is South Bend Mayor Pete Buttigieg, on 10%.

Buttigieg, who owes $130,000 in student loans between himself and his husband, does not support making public colleges free, though his plan calls for students from lower-income families to be able to attend school “debt-free.” The mayor also wants to lower the cost of attendance of colleges.

Sen. Kamala Harris received a bump in the polls after a strong performance in the first Democratic presidential debate last month, though that bump has since faded some. Harris has called for four-year public colleges to be “debt-free,” and allow those with student loan debt to refinance their loans at lower interest rates.

Democratic presidential frontrunner, former Vice President Joe Biden, has the support of 9% of 18 to 29 year old likely Democratic primary voters, according to the YouGov poll, though he leads the race overall on strong support from older voters.

Biden has not released an extensive education plan yet, though as vice president under President Barack Obama he called for 16 years of “free public education for all.” During his time in the Senate, Biden supported legislation making it harder to discharge student loan debt under bankruptcy protection.

Outside of the top polling candidates, former Housing and Urban Development Sec. Julián Castro unveiled a plan in May under which borrowers would not have to repay any of their student loans until they earned at least 250% of the federal poverty level.

Castro’s fellow Texan, former Rep. Beto O’Rourke unveiled a plan Wednesday to “encourage a more diverse teaching workforce” by giving student debt relief to teachers and investing in teaching programs at minority-serving institutions and historically black colleges and universities. O’Rourke has previously said he would work to make college tuition-free, and would consider wiping away some or all student debt.

New York Mayor Bill de Blasio has joined Warren and Sanders in calling for tuition-free public college, as has Rep. Tulsi Gabbard. Businessman Andrew Yang has expressed support for Warren’s debt-forgiveness plan, but declined to endorse supporting tuition-free public college.

Sen. Kirsten Gillibrand and Sen. Cory Booker have supported efforts to make public colleges “debt-free,” while Sen. Amy Klobuchar espouses a policy similar to Buttigieg’s — allowing borrowers to refinance their loans at lower rates, while supporting free community college.

Democrats will face opposition in implementing any of these plans if elected. A Quinnipiac poll in April found 52% of registered voters oppose tuition-free public colleges, while 45% support the proposal.