Albany, N.Y. ? With pressure mounting on Gov. Eliot Spitzer to resign over a call-girl scandal, investigators said Tuesday he was clearly a repeat customer who spent tens of thousands of dollars – perhaps as much as $80,000 – with the high-priced prostitution service over an extended period of time.

Spitzer and his family, meanwhile, remained secluded in their Fifth Avenue apartment, while Republicans began talking impeachment, and few if any fellow Democrats came forward to defend him. A death watch of sorts began at the state Capitol, where whispers of “What have you heard?” echoed through nearly every hallway of the ornate, 109-year-old building.

On Monday, when the scandal broke, prosecutors said in court papers that Spitzer had been caught on a wiretap spending $4,300 with the Emperors Club VIP call-girl service, with some of the money going toward a night with a prostitute named Kristen, and the rest to be used as credit toward future trysts. The papers also suggested that Spitzer had done this before.

Speaking on condition of anonymity, a law enforcement official said Tuesday that Spitzer, in fact, had spent tens of thousands of dollars with the Emperors Club. Another official said the amount could be as high as $80,000. But it was not clear over what period of time that was spent.

Still another law enforcement official said investigators found that during the tryst with Kristen on the night before Valentine’s Day, Spitzer used two rooms at the Mayflower Hotel in Washington – one for himself, the other for the prostitute. Around 10 p.m., Spitzer sneaked away from his security detail and went to the room where she was waiting, the official said.