April 11, 2016 7:55 PM EDT

Hillary Clinton and New York Mayor Bill de Blasio sparked controversy at an event on Saturday with a racially charged joke.

Clinton and de Blasio were joined onstage by Leslie Odom Jr. in costume as Aaron Burr, whom he plays in the hit Broadway musical Hamilton. Clinton thanked de Blasio for his endorsement—which many pointed out came rather late in the game—and ribbed him, “Took you long enough.”

The mayor replied, “Sorry, Hillary, I was running on C.P. time.”

The abbreviation refers to the stereotype of “Colored People time,” and several people in the audience could be heard gasping or groaning. Odom, who is black and whom the New York Times suggests was in on the joke, rebuked him, saying, “I don’t like jokes like that, Bill.”

Clinton dryly replied, “Cautious politician time. I’ve been there.”

The exchange prompted pushback online, both from bloggers and social media users.

Clinton, who has performed well with black voters in early primaries, will depend on their votes in the New York primary on April 19.

[NYT]

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