During a virtual meeting with the Congressional Black Caucus Monday night, President Joe Biden thanked members and asked for their continued support, according to two people on the call who spoke to ABC News.

       "I need you; I'm not going to disappoint you, I promise you," the president told the members, one of the call participants said.

       ABC News can first report that three Black Democratic senators also joined the call.

       Two sources tell ABC News that Sens. Laphonza Butler, Cory Booker and Raphael Warnock also joined President Biden's call with the Congressional Black Caucus. This is notable as the president looks to shore up support among black voters, the bedrock of the Democratic party.

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       The president told members that he was staying in the race. He thanked them for having "his back" and vowed to continue to have theirs. One person described the call as a "family conversation."

       While the president did take questions, two people on the call said no one expressed concerns about the president's campaign or spoke out against him.

       The call comes amid concerns over Biden staying in the race were raised privately and publicly by other House Democrats, including senior members of the party, following the debate.

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       So far, no Black Congressional Democrat has called on the president to step aside. And there's an immense effort underway to make sure the CBC holds the line, according to two members of the CBC.