Michael Bloomberg announced his exit from the race for the Democratic presidential nomination after amassing just 12 delegates so far from Super Tuesday primary states.

One of the wealthiest people in the world, Bloomberg self-funded his short campaign, spending $409 million as of the end of January, according to filings with the Federal Election Commission. By February, he’d spent more than $400 million on advertisements alone. He skipped the first four nominating states, having missed the deadline to file for primaries in New Hampshire and South Carolina.

“Three months ago, I entered the race to defeat Donald Trump,” Bloomberg tweeted Wednesday morning. “Today, I’m leaving for the same reason. Defeating Trump starts with uniting behind the candidate with the best shot to do it. It’s clear that is my friend and a great American, Joe Biden.”

Sen. Amy Klobuchar, D-Minn., and former South Bend, Indiana Mayor Pete Buttigieg both dropped out of the race in the days before Super Tuesday and endorsed the former vice president. Just Joe Biden and Sanders won popular votes in Super Tuesday states, focusing the race between those two candidates.