Warren rallies with Chicago teachers

Warren, a Massachusetts senator and former teacher, joined a crowd of hundreds of teachers and parents outside an elementary school to back the Chicago teachers' demands for more resources, and promised to boost funding for U.S. public schools if elected president in 2020.

"I'm here to stand with every one of the people who stand for our children every day," Warren said to thunderous applause and cheers.

The teacher's union called the work stoppage last week after contract negotiations failed to produce a deal on pay, overcrowding in schools and a lack of support staff such as nurses and social workers.

Warren, a leading progressive voice for the Democrats, is one of the top contenders aiming to secure her party's presidential nomination and face off in next year's U.S. election against President Donald Trump.

Her campaign proposals include making an $800 billion investment in public schools and canceling all student loan debt.