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For a brief, blissful second, the Democratic 2020 pool narrowed to 23 candidates. That time is over.

After a slew of Monday reports indicated that liberal billionaire Tom Steyer was inching toward a 2020 run, he officially announced his Democratic campaign for president with a four-minute campaign video released Tuesday morning. The announcement comes after Steyer indicated earlier this year he wouldn't run in 2020, but well after his November ad campaign that looked an awful lot like a presidential platform.

Steyer starts the video by explaining how he grew up during the Civil Rights era, and how that showed that the "underlying injustice of America was coming under attack." He also doesn't shy away from the fact that he's a billionaire, but instead emphasizes that he signed the Giving Pledge to donate half of his wealth while he's alive, while saying many other wealthy people would "rather make money than save the world" from climate change. To emphasize that point, the ad flows through footage of Jeffrey Epstein, Martin Shkreli, and other wealthy people and Republican politicians.

In November, Steyer unveiled a website and six-figure online ad campaign touting what he called the "five rights" essential to "an equal chance to earn their fair share of America's prosperity." He's also spent much of President Trump's term calling for his impeachment, including with a $12 million TV ad buy aimed at congressional Democrats.

The announcement comes after Rep. Eric Swalwell (D-Calif.) announced Monday he was ending his 2020 campaign, focusing instead on his reelection next year to the House.