Former New York City mayor Michael Bloomberg has been spending a lot of money on presidential campaign ads targeting President Donald Trump, but pivoted Monday to take on primary challenger Sen. Bernie Sanders, calling out the online actions of some of the progressive’s supporters.

In the ad, posted early Monday morning, tweets from a handful of Sanders backers, featuring memes and hashtags like #BernieOrElse, appear on the screen. “Vote Bernie or bad things will happen,” warns one tweet.

Another says, “Libs who are flirting with Bloomberg now should be aware that they are going on lists. Next time they pretend to care about racism or sexual harassment or really anything other than money and power, we will remember what they were doing right now and we will remind everyone.”

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Those are followed by screenshots of what appear to be harassing text messages purportedly sent by Sanders supporters to Democrats not inclined to vote for him in the primary, as well as headlines from prominent news outlets highlighting the harassment.

The ad references The Daily Dot’s “Are You Being Harassed by a Bernie Bro or a Bernie Bot?” and Bret Stephens’ New York Times column, “Bernie’s Angry Bros,” tapping into the stereotype of Sanders’ most ardent supporters leftover from 2016. Finally, it shows Sanders himself hailing the importance of “civil discourse,” but ends with one word on screen: “Really?”

Bloomberg has been condemned for what critics call attempts to “buy” the presidency, as well as his past defense of policies like “stop and frisk,” and practice that allows police officers to search people at random and is largely considered racist. In recently unearthed audio from a 2013 interview, Bloomberg defended the policy, saying “I think we disproportionately stop whites too much and minorities too little. It’s exactly the reverse of what they’re saying. I don’t know where they went to school but they certainly didn’t take a math course or a logic course.”

Sanders’ progressive supporters are not the only people to take issue with Bloomberg for those reasons. President Trump himself called Bloomberg a racist on Twitter for the stop and frisk defense.

We need to unite to defeat Trump in November. This type of “energy” is not going to get us there. https://t.co/bPuUZMs2d6 pic.twitter.com/Tdp6mpWjcX – Mike Bloomberg (@MikeBloomberg) February 17, 2020

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