"I am deeply sorry I did not live up to what was expected of me," said Spitzer, referring to his "private failings" for which, he also said, "I've begun to atone."
The announcement (see video of the statement below) follows a stunning two days of revelations about Spitzer's personal activities. At a press conference Monday with his wife, Silda, at his side (as she was for Wednesday's announcement), Spitzer said: "I have acted in a way that violates my obligations to my family and violates my – or any – sense of right and wrong."
He added, "I apologize to the public, whom I promised better."
The resignation effectively ends Spitzer's political career just 16 months after he was elected New York's Democratic governor by a wide margin.
With Spitzer out of office, New York's state constitution calls for his job to pass to his lieutenant governor and running mate, Lt. Gov. David A. Paterson, 53, a legally blind former legislator. Paterson, whom the Wall Street Journal described as being "as widely liked as Mr. Spitzer is controversial," also becomes the Empire State's first African-American governor.
The transfer of power will take place on Monday, Spitzer said, as he also announced that this was the desire of Paterson.
Possible Plea DealMarried for 21 years and the father of three daughters, Spitzer, 48, hired a prostitute from a New Jersey escort service and arranged for her to meet him in the nation's capital on Feb. 13, for a fee of $4,300, according to a federal complaint and two lawyers briefed on the case. Additional reports suggest Spitzer may have spent at much as $80,000 for prostitutes.
Among the questions raised was whether Spitzer used government security while he was engaged in his private activities.
Spitzer has not been charged with a crime, however. It remains unclear whether state or federal authorities will seek to prosecute him for his alleged involvement. CNN, suggesting that a possible plea deal was in the works, has reported that Spitzer has hired a powerful Manhattan legal firm.
In editorials that appeared the day after the revelations, calls for Spitzer's resignation were made by New York's Daily News, the New York Post and Newsday.
Commenting on what it termed a "sad and sordid spectacle," Wednesday's The New York Times criticized Spitzer for remaining secluded in his Fifth Avenue Manhattan apartment all day Tuesday (as the state government remained at a standstill) and not alerting the public or even his possible successor as to his future plans.
Get more coverage of the Spitzer scandal at CNN.com