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 organized labor and prominent liberal groups 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 comparing the institution to slavery.

"This is one of those bad compromises we made at day one in this country," he said. "There are many others we can think of and they are all connected, including the value of some people based on the color of their skin. There is a legacy and a series of consequences that have persisted and remain with us to this day."

"In this conversation about how we repair the damage, how we make things right, and how we keep from committing the same injustice going forward is squarely connected to the reason that we are all convened here today and that is fixing our democracy," O'Rourke continued. "So yes, if we get rid of the Electoral College, we get a little bit closer to one person, one vote in the United States of America."

Sen. Elizabeth Warren (Mass.) was the first 2020 Democrat to endorse abolishing the Electoral College in March during a CNN town hall. Since then other Democratic White House aspirants, including Washington Gov. Jay Inslee and former Secretary of Housing and Urban Development Julian Castro, have come out in favor of eliminating it.