Michael Bloomberg is running for president and Bernie Sanders is thrilled.

At the end of the day, the 1% is only 1%. We are 99% and that is exactly why we will win. https://t.co/xiq5i7oyPw — Bernie Sanders (@BernieSanders) November 8, 2019

Even after candidates like Bill De Blasio, Tim Ryan and John Hickenlooper dropped out, the Democratic primary field is still crowded. Nearly twenty candidates are running and throwing another big name into the fray—let alone a billionaire former New York mayor—would seem like something to worry about. Bloomberg’s name recognition, ungodly wealth and eponymous media empire make him a real threat to further splinter key primary votes, even with such a late entry date.

But Sanders and his campaign have gone on the offensive, painting the billionaire’s candidacy as a sign that the Vermont senator’s campaign is surging.

And they’re right to do so.

The billionaire class is scared and they should be scared. — Bernie Sanders (@BernieSanders) November 7, 2019

If Bloomberg runs as a Democrat, it could bode well for Sanders. The Vermont senator’s base is strong and loyal. While the billionaire former mayor isn’t likely to pull many votes from Sanders’ constituency, he could help clear the way to a Bernie nomination by splitting the loyalties of moderate primary voters who may have otherwise backed former Vice President Joe Biden or South Bend, Ind. Mayor Pete Buttigieg.

Mere hours after Bloomberg’s announcement, Sanders’ campaign manager Dave Sirota sent out a “Bern Notice” email blast underscoring billionaires’ fear. The senator’s campaign centered nearly all of its weekend social media posts and fundraising emails around Bloomberg’s candidacy. And like clockwork, Vox’s Jason Del Rey reported Sunday that on a private phone call earlier this year, Amazon founder Jeff Bezos asked Bloomberg if the former New York mayor would consider a presidential run. Sanders’ social media team couldn’t ignore the hilarity or the evident solidarity among billionaires.

Hahahahaha. That's some real class solidarity. I’m impressed by that grassroots movement. Our campaign on the other hand is a real movement by and for the working class. We are going to take on the billionaire class, and we are going to defeat them. https://t.co/Z9EjXFqwFH — Bernie Sanders (@BernieSanders) November 10, 2019

It’s clear that billionaires are starting to feel the heat more than ever. Sanders and Warren have established themselves as two clear long term frontrunners in the Democratic primary. Terms like “universal healthcare” and “wealth tax” are quickly becoming common parlance. High profile billionaires like Bill Gates and Mark Cuban have spoken out against wealth taxes. Leon Cooperman actually teared up on MSNBC airwaves while discussing what a Warren presidency would do to his absurd level of personal wealth.

But while Warren has shown slightly more sympathy towards the plight of billionaires, offering to chat with Bill Gates and promising she won’t levy a $100 billion tax on the Microsoft founder, Sanders is resolute in attacking America’s wealthiest one percent. And while those attacks may rile billionaires and their media mouthpieces, it’s a message with a good chance to reverberate with everyday Americans. There’s overwhelming support for raising taxes on the ultra-wealthy, even among a majority of Republicans.

Michael Bloomberg, the richest man in New York City, spent $261 million of his own money pursuing public office, more than anyone else in the United States. Despite spending a record $102 million to win a third term, only barely squeaked over the finish line. And if former Massachusetts Governor and Bain Capital Managing Director Deval Patrick enters the race, Bloomberg couldn’t even count on the undivided support of northeast financial elites.

You really couldn’t imagine a better person for Bernie to run against. Except maybe Trump.