Borgia sent an email last week following Astorino's veto of the Immigrant Protection Act, which Borgia supported. Astorino said the act would make Westchester a "sanctuary county," and it could lose federal funding.
"It's the classic 'Big Lie' technique," Borgia wrote. "All clever Nazis use it."
Borgia said she regretted using provocative language.
At a rally Wednesday, Astorino said Borgia's statement was a non-apology.
"I'm really disappointed in this kind of discourse in Westchester," Astorino said. "Any apology should go to the people of Westchester."
Borgia's comments received bipartisan condemnation, including from the Holocaust and Human Rights Center in White Plains.
State Sen. George Latimer, who is running for the Democratic nomination for county executive, said it was a "poor choice of words."
Ken Jenkins, who is also running for the Democratic nomination, did not respond to multiple requests for comment.
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