Vermont Sen. Bernie Sanders announced on Tuesday he would run for the presidency once again, launching a progressive campaign that challenges economic and social inequality.

Sanders, an independent, is known for his anti-establishment values and as the 2016 Democratic primary runner-up to Hillary Clinton. In a video shared by Sanders’ campaign on Tuesday morning, the presidential hopeful laid out his values once again in a series of news sound bites paired with inspirational music.

“Real change never takes place from the top on down, but always from the bottom on up,” Sanders says in the introduction of the video.

The clip goes onto highlight his progressive pushes for universal healthcare, free college tuition, a call for action on climate change, as well as economic and social equality. In the video, he says the U.S. economy “is rigged” and that the current campaign finance system is corrupt.

In a separate, longer video that lays out his campaign values, Sanders asks supporters to be part of “an unprecedented grassroots campaign” with the ambitious goal to form 1 million campaign volunteers across all 50 states.

“Our campaign is about transforming our country and creating a government based on the principles of economic, social, racial and environmental justice,” Sanders said in the video.

Sanders, 77, enters an already-crowded field of Democratic presidential contenders including Massachusetts Sen. Elizabeth Warren, who offers similar populist politics.