Sandra Schultz Newman called the e-mail, written by a Republican consultant, misguided and said she regrets she did not carefully review the final draft before it was released.
"Some of the language was inappropriate and intemperate," Newman wrote in an e-mail statement Monday. "I apologize to anyone who was offended by this misguided e-mail."
The e-mail sent Thursday to 75,000 Jewish voters in Pennsylvania warns "Fellow Jewish Voters" of the danger of a second Holocaust due to the threats to Israel from its neighbors and touts McCain's qualifications over those of Obama, the Democratic presidential candidate.
Republicans quickly disavowed the e-mail and said they fired the campaign consultant who wrote it. A campaign spokesman for Republican presidential nomineealso repudiated it.
In Monday's statement, Schultz said the original e-mail was drafted by "a worker for the McCain campaign." Asked by a reporter later in the day to identify the worker, Schultz said she was referring to Bryan Rudnick, the fired consultant.
"I believe Bryan was let go before it was approved,'' she said in response to a query from The Associated Press. ``I was not involved in hiring Bryan and so I am not sure for whom he worked.''
A spokesman for the state GOP confirmed that Rudnick was employed by the state party.
"He was our employee and we let him go" on Friday, said the spokesman, Mike Barley.
Rudnick has told the AP that he had authorization from party officials to send the e-mail. He said he was fired Friday morning over "discrepancies with strategy and logistics," and that the e-mail was not mentioned when he was let go.
A copy of the e-mail provided by Democratic officials says it was "Paid for by the Republican Federal Committee of PA - Victory 2008." The signatures of Schultz and two other McCain supporters were on the message.
Sen. Robert Casey, D-Pa., criticized the e-mail as part of a smear campaign that was among the worst he had seen in his state.
Newman also has been involved in the state Republican Party's civil lawsuit against the community-activist group ACORN and Secretary of State Pedro Cortes, the state's top election official.
A hearing in state Commonwealth Court is scheduled for Wednesday on the suit, in which the GOP accuses ACORN of fostering voter-registration fraud. State officials say the county-run election system has built-in safeguards to prevent fraudulent ballots from being cast. Democratic leaders say the allegations are simply demagoguery.