WASHINGTON (Reuters) - Democratic presidential candidate Bill de Blasio apologized on Thursday for unwittingly quoting Ernesto “Che” Guevara, a Marxist revolutionary reviled by many Cuban-Americans for helping Fidel Castro come to power in Cuba.

FILE PHOTO: New York City Mayor and Democratic presidential candidate Bill de Blasio attends a rally in New York City, U.S., May 21, 2019. REUTERS/Jeenah Moon /File Photo

The New York City mayor, fresh off a solid showing in Wednesday night’s Democratic debate, used the Spanish phrase “hasta la victoria siempre” (“to victory, always”) in Miami as he addressed striking airport workers, who cheered him heartily.

Local Democrats, including the chairwoman of the state party, promptly criticized his use of the phrase and called for an apology.

“Quoting a murderer responsible for death & oppression in communist Cuba and throughout Latin America is not acceptable. Please apologize. Many on strike are Cuban btw,” Florida state Senator Jose Javier Rodriguez wrote in a Twitter post.

De Blasio explained the misstep on Twitter.

“I did not know the phrase I used in Miami today was associated with Che Guevara & I did not mean to offend anyone who heard it that way,” he wrote. “I certainly apologize for not understanding that history.”

Born in Argentina in 1928, Guevara became a Marxist after a motorcycle ride through South America opened his eyes to poverty when he was still a medical student. He subsequently joined Castro’s revolutionary movement, which led to the overthrow of Cuban dictator Fulgencio Batista in 1959.

Guevara is a hated figure to many in the large Cuban exile community in South Florida, a traditionally conservative Republican voting bloc that gradually has been opening up to Democrats. More than half of Florida’s Cuban Latinos supported Republican President Donald Trump in 2016.

Republicans pounced on the gaffe. Tim Murtaugh, communications director for Trump’s re-election campaign, said “quoting murderous communist sociopaths” probably meant de Blasio was losing.

Florida’s former governor, U.S. Senator Rick Scott, said on Twitter: “In case there was any doubt about the Democrats running for President embracing socialism, @BilldeBlasio is in Miami quoting ... Che Guevara. You can’t make this up.”