DES MOINES, Iowa (CBSNewYork/AP) — New York City Mayor Bill de Blasio is calling income disparity a “profound challenge facing our country.”

De Blasio appeared Thursday at Drake University in Iowa at the invitation of former U.S. Sen. Tom Harkin. He spoke before about 50 people.

“We all know that tackling income inequality is no small thing,” de Blasio said in prepared remarks. “We face a massive crisis – one that wasn’t created overnight, and one that won’t be fixed overnight.”

De Blasio said the daily struggle of hardworking people to keep their heads above water is a national problem that requires a national commitment to solve it.

Among his proposals to address income inequality were raising the minimum wage and offering paid sick leave to all workers.

“This is something that I’m going to speak about every chance I get, everywhere I go, because this is a crisis facing our nation and facing our city. It’s a profound crisis, it’s a crisis that is not being addressed, and it is a dangerous, dangerous situation,” de Blasio said earlier this week before his trip.

De Blasio is seeking to be a voice for the liberal wing of the Democratic Party, alongside U.S. Sen. Elizabeth Warren, of Massachusetts. His efforts to raise his national profile include making a play for the 2016 Democratic National Convention and hosting a meeting of liberals at the mayor’s residence, Gracie Mansion, this month.

The first-term mayor took heat this week for not immediately endorsing Hillary Rodham Clinton for president.

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