Democratic primary contender Pete Buttigieg called out Michigan native Betsy DeVos in national campaign ads for her policies as secretary of education.

Democratic presidential hopefuls targeted DeVos the most out of President Donald Trump’s cabinet members while jockeying for the support of teacher unions during the 2020 primary. Buttigieg’s campaign began running a series of Facebook ads this week to coincide with the first day of school, though Michigan is one of the few states where classrooms aren’t back in session until after Labor Day.

Buttigieg’s campaign criticized DeVos for saddling college students with debt. The ads call out Devos for rolling back Obama-era policies protecting students from predatory loan practices and for-profit colleges. Federal judges have blocked DeVos’ delays of Obama administration regulations, including those governing loan forgiveness for defrauded borrowers, and other legal challenges are ongoing.

More than 150,000 former students of for-profit colleges filed a lawsuit against the U.S. Department of Education and DeVos in June. The lawsuit claims the agency is preventing students who were defrauded by for-profit colleges from using federal debt relief.

The 37-year-old mayor of South Bend, Ind., and his husband owe $130,000 in student loans, according to the Associated Press. His personal experience has colored Buttigieg’s placement of eliminating student loan debt among his top campaign promises. Buttigieg graduated from Harvard in 2004 and Oxford in 2007.

Buttigieg proposed expanding funding for Pell Grants to make it possible for low and middle income students to graduate without debt and investing $25 billion in Historically Black Colleges and Universities.

“The ads come at a make-or-break moment for our public education system,” Buttigieg’s campaign said in a statement. “The same old debates have left the country with underfunded schools, underpaid teachers, and growing inequality. Public education is key to meeting the challenges of today and the future, which is why Pete is offering a new approach and bold ideas that transform how we value our teachers, fund our schools, and educate our students.”

Forgiving student loan debt supported by several of the top-polling Democrats seeking their party’s nomination for president in 2020. U.S. Sens. Bernie Sanders, I-Vt., and Elizabeth Warren, D-Mass., proposed legislation to erase the debt of 45 million Americans.

Last week, Trump issued an executive order to wipe out student loans for around 25,000 permanently disabled veterans.

During the second Democratic National Committee debate in Detroit last month, Buttigieg said those plans don’t fix the root cause of the issue. He said expanding loan forgiveness programs is important, but having debt-free college for low and middle-income students would address the problem up front.

Buttigieg also criticized DeVos for rolling back loan protections at the debate.

Buttigieg is polling fifth in the crowded Democratic primary, slightly behind U.S. Sen. Kamala Harris, D-Calif. Former Vice President Joe Biden leads the field, followed by Sanders and Warren.

Trump’s decision to tap DeVos for education secretary met backlash from Democrats and teachers unions. The U.S. Senate split evenly 50-50 on DeVos’ confirmation -- all senators running for president voted against her -- requiring a tie-breaking vote from Vice President Mike Pence.

Warren called DeVos the “worst secretary of education we’ve seen." Several Democrats pledged to replace her with someone who has more classroom experience, and Warren promised to put a former public school teacher in the nation’s top education post.