Presidential candidate Sen. Bernie Sanders (I-Vt.) took the stage on Saturday at the Netroots Nation conference in Phoenix to discuss race and human rights, amid protesters in the room.

Fellow presidential hopeful and former Maryland Governor Martin O’Malley spoke just before Sanders, and made the mistake of using the term “all lives matter,” a term the black community considers an affront to the #BlackLivesMatter rallying cry. So when it was Sanders’ turn to speak, the white 73-year-old did not receive the warmest of welcomes.

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He started off with his usual stump speech, according to CNN, but once he gauged the hostility of the room, he switched over to improvised remarks.

“Black people are dying in this country because we have a criminal justice system which is out of control, a system in which over 50 percent of young African-American kids are unemployed,” he said. “It is estimated that a black baby born today has a one in four chance of ending up in the criminal justice system.”

But it did little to quell the protesters. And when the Twitterverse later caught wind of Sanders’ fumble, they decided to take some jabs at him, using the hashtag #BernieSoBlack.

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Others soon caught on, and started sharing their own fictitious visions of what makes Sanders “so black.”

I heard Bernie Sanders told Joe – you and Katherine got so many kids you should put a band together, lil Michael got talent #BernieSoBlack — D-Money (@the_otherDP) July 19, 2015

the studio audience on good times? that was all him. #BernieSoBlack — Desus Nice (@desusnice) July 19, 2015

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#BernieSoBlack that he taught Harriet Tubman how to "follow the drinking gourd." — Preston Mitchum (@PrestonMitchum) July 19, 2015

https://twitter.com/siftyboones/status/622830919166988288

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Sanders also delivered a speech Saturday night in front of his biggest crowd on the campaign trail yet. Approximately 11,000 turned out at the Phoenix Convention Center to hear his talk about a variety of issues, including race.

Sanders devoted more than four minutes of his speech in Arizona—a border state plagued with racial tension—to discussing race relations in America. He specifically touched on the challenges facing black people. “It is not acceptable to me that we’ve seen young black men walk down streets in this country, be beaten, and be killed, unjustly.”

He also touched on income inequality, access to healthcare, and access to suitable childcare for working parents, issues that disproportionately affect the black community.

The Sanders campaign is making a concerted effort to reach minority voters. Campaign manager Jeff Weaves told the New York Times in June that they were trying to create some name recognition for Sanders within the black community.

“We’re reaching out, but it’s no secret that Bernie represents a state that is heavily Caucasian, and his decades of work on issues of importance to African-Americans aren’t known amid the national conversation on race that is underway,” Weaver said.

Despite Sanders’ history of civil rights activism (he participated in the historic March on Washington in 1963), he’s still not a shoe-in for minority vote. Until he is, he may have to endure some gentle—or not-so-gentle—criticism.

that Sanders "arugula" moment lol — Talib Kweli Greene (@TalibKweli) July 19, 2015

Photo via DonkeyHotey/Flickr (CC BY 2.0)