Speaking to a racially diverse audience in Des Moines on Sunday, Joe Biden talked of his long-standing support from African American voters and how the Civil Rights movement inspired him to become politically active.

Biden, who is seeking the Democratic presidential nomination, spoke at a block party hosted by the Des Moines NAACP, and Des Moines area nonprofits Creative Visions and Urban Dreams.

In response to a question, he said he has long-standing relationships in the African American community and in faith-based communities.

"I was raised in the black church politically," Biden said. "Not a joke."

Biden, who was vice president for former President Barack Obama, the nation's first president who is African American, has strong support among African American voters, national polling shows. A recent Washington Post-Ipsos poll found Biden leads among black Democrats nationally with 48%, a 28-point lead over his nearest rival, U.S. Sen. Bernie Sanders.

More: In Iowa, Pete Buttigieg addresses questions about low black support.

"It’s the single most loyal constituency I have ever had," he said.

Biden said he knows there are people "wondering why does Biden get such overwhelming support from African Americans."

"That's what got me involved in politics to begin with: The Civil Rights movement," he said.

At an event in Marshalltown on Sunday night, Biden noted that the African American population of Delaware, which reelected him to the Senate for decades, is almost 20%. He also recalled his experience working as a lifeguard at a predominantly African American swimming pool in Wilmington.

As he has before, Biden recalled how he was inspired to get more involved in politics after Dr. Martin Luther King Jr. and U.S. Sen. Bobby Kennedy were assassinated in 1968. His hometown of Wilmington, Delaware, was occupied by the National Guard for nine months after King's assassination, and Biden said at that time he was inspired to quit the job he was offered "at a really good, fancy law firm" and become a public defender instead.

Biden is embarking on an eight-day "Soul of the Nation" bus tour across Iowa leading up to the Iowa caucuses on Feb. 3, which kick off the presidential nominating process.

Stephen Gruber-Miller covers the Iowa Statehouse and politics for the Register. He can be reached by email at sgrubermil@registermedia.com or by phone at 515-284-8169. Follow him on Twitter at @sgrubermiller.

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