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Jack Abramoff, former Republican "superlobbyist" and now a convicted and sentenced felon cooperating with federal prosecutors, is the central figure in a web of corruption within the U.S. Republican Party, which will likely be the most far-reaching Washington corruption scandal of recent decades. In January 2006, Abramoff reached a plea agreement with Federal prosecutors, in which he pled guilty to a number of felonies and agreed to cooperate with the authorities. It is likely that this cooperation will lead to prosecution of numerous Republican lawmakers, staffers, lobbyists, and operatives. Abramoff's principal activity was the collection of tens of millions extorted from Indian tribal gambling operations. Much of the money was used to buy influence from Washington Republican figures, but a considerable amount was used for self-enrichment or personal pet projects.
The disgraced long-time Washington insider whom Congressman Tom DeLay once referred to as one of his "closest and dearest friends," collected $100,000+ for President George W. Bush's re-election campaign, "earning premier status within the campaign" as a Bush Pioneer, as well as raised funds for GOP congressional candidates. 
As a Republican Party lobbyist, Abramoff was Senior Director of Government Affairs for the Greenberg Traurig law and lobbying firm from January 2001 to March 2004, when he was fired and became a consultant at the Cassidy & Associates lobbying shop. Abramoff was "brought into Cassidy" by Gregg Hartley, a former top aide to House Majority Whip Roy Blunt (R-Missouri)," according to Roll Call's Brody Mullins. 
Abramoff cut his ties with Cassidy & Associates on or around July 8, 2004, "to form his own company, Middle Gate Ventures," to do "such business opportunities as energy projects, real estate development and motion picture production -- no lobbying," according to the Washington Post's Judy Sarasohn. In March 2004, Abramoff had "signed an exclusive contract with Cassidy for him to steer lobbying business to the company."
Abramoff and his partner Adam Kidan were sentenced March 29, 2006, by Judge Paul Huck of the Federal District Court in Miami, Florida, to 70 months in federal prison, placed on three years' probation, and "ordered to pay a total of $21.7 million in restitution" for their role in a fraud scheme involving the "$147.5 million purchase of the shipping line, SunCruz Casinos, in 2000." 
Abramoff initially remained free "so that he [could] continue to aid in the investigations that swirl around him and his former lobbying practice." 
He reported to a federal prison in West Virginia on November 15, 2006 to begin serving his sentence. Prosecutors had requested he be held there rather than at a similar facility in Pennsylvania in order that they would have easier access to him during their continuing investigation into his associates. 
On September 4th, 2008, Abramoff was sentenced to four years in prison for corruption. Though Abramoff faced a maximum possible sentence of eleven years, U.S. District Judge Ellen Segal Huvelle showed leniency because of his assistance with the FBI investigation. The sentence is in addition the prison sentence he received in 2006. Abramoff could still appeal the decision.
Guilty Plea Deals
On January 4, 2006, a day after he entered guilty pleas to "defrauding Indian tribal clients of millions of dollars, conspiring to bribe members of Congress and evading taxes" before a federal judge in Washington, DC, A