Wealthy Fort Lauderdale businessman Joel Steinger, the target of a fraud investigation, realized he was in a jam. So he went to the FBI in 2007 with an incredible story: He and major fundraiser Alan Mendelsohn had bribed Charlie Crist when he was Florida's attorney general.

Intrigued, the FBI wired up Steinger and had him record tantalizing conversations with Mendelsohn that seemed to support the allegation: Mendelsohn, in fact, boasted of bribing Crist to shut down state and federal investigations into Steinger's insurance company, Mutual Benefits Corp.

But here's what nobody but Mendelsohn knew: His claims about the governor were all a lie.

A federal indictment charges Mendelsohn, 51, a Hollywood eye surgeon, with running his own con, manipulating Steinger into donating more than $1.5 million to the doctor's political committees with false promises that Crist and his top aides would thwart the state probe.

Later, confronted with recordings of his own words, Mendelsohn finally admitted it was all puffery. But the FBI was so skeptical -- was Mendelsohn lying about his lies? -- that agents had him call the governor's chief of staff, George LeMieux, to see if he would implicate himself as a bribe-taker.

LeMieux saw right through Mendelsohn's clumsy attempt.

It was the beginning of the end for Mendelsohn -- a miscalculation that undermined his credibility with the FBI and turned the spotlight onto him instead of the governor.

The outcome: A two-year probe into his alleged influence-peddling schemes -- primarily for Republican contributors and candidates -- that led to his 32-count indictment last month.

Mendelsohn is charged with defrauding fat-cat contributors who gave more than $2 million to his three political action committees. Like Steinger, they believed they were buying Mendelsohn's clout and connections. The doctor allegedly spent at least $624,000 of the donations on himself and his mistress -- as well as funneling $87,000 to an unnamed ``public official'' in Florida.

His trial is set for May. The Justice Department says it expects to add new defendants and charges by year's end.

For coming forward with the information against Mendelsohn, Steinger, 59, received immunity from the Justice Department and cannot be charged with anything he told public corruption prosecutors. But the former head of Mutual Benefits, which sold life insurance policies of people dying of AIDS, still faces separate federal charges for an alleged $837 million Ponzi scheme.

FALSE CONNECTIONS

According to the indictment and sources familiar with the case, here's what happened when Steinger -- working for the FBI -- recorded Mendelsohn:

In May 2007, Mendelsohn called Steinger to ask him for a $400,000 donation to one of his political action committees, Alliance for Florida's Future. Mendelsohn claimed ``he would use the money to pay for television advertisements in connection with a political campaign for public office,'' the indictment says.

Mendelsohn wanted to raise the money for Republican Richard Corcoran of Crystal River, who was running against two other candidates in a GOP primary for an open Senate seat that June.

Steinger told Mendelsohn that ``he could not easily make such contributions'' because a federal court-appointed receiver in Miami had control over his company's assets, and because of a federal investigation into him and his business colleagues.