Former Texas congressman Beto O’Rourke joined a growing list of 2020 Democrats by endorsing the abolition of the Electoral College on Monday.

O’Rourke, who previously said there was “a lot of wisdom” behind eliminating the Electoral College, endorsed the idea outright while addressing the annual We the People Membership Summit in Washington, D.C.

“Let’s abolish the Electoral College,” O’Rourke told the audience in response to question about gerrymandering and the popular vote. The event was hosted by labor organization and prominent liberals organizations like the Sierra Club, Planned Parenthood Action Fund, and the Center for Popular Democracy Action, a dark money group funded in part by George Soros.

O’Rourke justified his call for eliminating the Electoral College by the comparing the institution to slavery.