“You think you just fell out of a coconut tree?” Vice President Kamala Harris said last year at a White House event, chuckling as she quoted her mother. “You exist in the context of all in which you live and what came before you.”

Perhaps it was the way she laughed at herself, or the way a folksy saying took a sudden philosophical turn. Whatever the reason, over a year later it has become the line that launched a thousand memes.

On social media platforms including X and Instagram, some users have added coconut and palm tree emojis to their bios and beside their handles, referring to the speech. Clips of Ms. Harris speaking have been remixed into pop songs by artists like Charli XCX and Chappell Roan, and they have spread widely across TikTok.

It’s the latest iteration of a longtime online fandom around Ms. Harris, sometimes known as the KHive. The online encyclopedia Know Your Meme credits the MSNBC correspondent Joy-Ann Reid with coining the moniker — a play on BeyHive, the name of Beyoncé’s devoted fan base — in a tweet in 2017, when Ms. Harris was a first-term senator from California. Both Ms. Harris and President Biden have referred to the KHive on social media over the years.

The KHive grew in number in 2019, during Ms. Harris’s unsuccessful run to secure the Democratic nomination for president, but became quieter when she became Mr. Biden’s vice president and struggled at times to make the role her own. Since Mr. Biden suspended his re-election campaign on Sunday and endorsed Ms. Harris to be the Democratic presidential nominee, her supporters have become increasingly vocal, reinvigorating the online community.

Courtney Phillips, a stay-at-home mother in Gastonia, N.C., who is a founder of the grass-roots organization Mamas4Kamala, said she had been part of the movement since Ms. Harris’s first presidential campaign.