Sen. Bernie Sanders received a warm welcome on Thursday at the National Action Network's convention led by Rev. Al Sharpton.

Sanders told the audience he marched on Washington with Dr. King, supported Jesse Jackson when he ran for president in 1988, and voted against Bill Clinton’s welfare reform bill. He also returned to the familiar themes of his campaign, including income inequality and free college.

“I want kids in the fourth grade here in New York City to understand that, even if their parents never went to college, even if their family has no money, if those kids study hard, take school seriously, regardless of the income of those kids, they will be able to get a college education,” he said.

Michael Charles, 66, from Queens, was planning to vote for Hillary Clinton, but said there was a strong probability he’ll vote for Sanders after hearing him speak. “He has attacked some very critical, sensitive issues which need to be addressed, and that’s the wide inequality of incomes,” he said.

Sanders trails Clinton in the polls ahead of the Tuesday primary.