In virtual caucus meetings, Biden and Harris reach out to voters of color.

Joseph R. Biden Jr. and Kamala Harris sought to appeal to Black, Latino and Asian-American voters on Wednesday, taking a swing through three virtual caucus meetings held during a socially distant Democratic convention.

In pre-recorded remarks to the D.N.C.’s Hispanic Caucus, Mr. Biden echoed several speakers in asserting that Latinos held “extraordinary power to shape this election.”

“There’s no question that this is a challenging time. And it is so often the case when hard times hit, Latino families are bearing a disproportionate share of the burden,” he said. “We owe it to those families to stand up and fight for them.”

About an hour later, in remarks to the D.N.C. Black Caucus, Mr. Biden recalled the late Representative John Lewis, a civil rights icon, and urged viewers to “carry his legacy forward” by pressing ahead to “unify this nation” and “fight for greater equity and justice.”