Bernie Sanders

PORTLAND, Maine — Independent U.S. Sen. Bernie Sanders gained roars of approval from a friendly crowd on Monday as he called for a radical transformation of the Democratic Party into a grassroots movement founded on the tenets of his unsuccessful Democratic presidential campaign: fighting against the billionaire class and rigged economic and political systems.

Sanders, of Vermont, and Democratic National Committee Chairman Tom Perez, who faced some boos as he spoke, launched a cross-country tour together in Maine, where Sanders won the Democratic presidential caucuses. The tour will take them from Maine to eight other states, including Florida, Arizona, Montana and Nevada.

Sanders, who ran as a Democrat against Hillary Clinton but returned to the Senate as an independent, said the Democratic Party must stop ignoring half the nation’s states and take on corporate greed on behalf of the working class. Perez urged attendees to resist Republican President Donald Trump by winning seats in Congress, statehouses and school boards.

“That’s what we will do: Fight like hell with you,” Perez said.

A crowd of roughly 1,200 filled the State Theatre, with the loudest cheers for Sanders and jeers at mentions of the “1 percent” and Trump’s executive orders and proposed budget cuts.

“Our vision for the future of this country is a very different vision than yours,” Sanders said, as he called for living wages, protecting Planned Parenthood and fighting income inequality.

He also said he’s introducing legislation to create a single-payer health care system.