UPDATED 10/03/11 2:25 p.m.

CHICAGO (CBS) — Jury selection has begun in the trial of Springfield businessman and powerful political insider William Cellini, on charges that he shook down a Hollywood producer for campaign contributions.

Jury selection was supposed to start late Monday morning, but was pushed back to Monday afternoon. The 76-year-ol sat at the defense table wearing reading glasses and flipping through documents as jury selection started.

Cellini has pleaded not guilty to multiple charges. If convicted on all counts, he faces a maximum prison term of more than 50 years.

The trial is expected to last about three weeks.

As WBBM Newsradio’s Nancy Harty reports, the former high school teacher turned mega millionaire has flown under the radar most of the time, but has cozied up to successive Illinois governors from both parties. But so powerful was he behind the scenes that he was referred to in awe as The King of Clout and the pope of Illinois politics.

LISTEN: WBBM Newsradio’s Nancy Harty reports

Cellini is accused of trying to shake down the Oscar-winning producer of “Million Dollar Baby” for a $1.5 million campaign contribution to former Gov. Rod Blagojevich, and his trial is the last in a series stemming from a decade-long investigation of the deposed Democratic governor.

Blagojevich was convicted at retrial earlier this year of trying to sell or trade President Barack Obama’s old Senate seat.

Cellini stepped down as Illinois Secretary of Transportation in 1973, but University of Illinois at Springfield political science professor Ron Michaelson says Cellini was just getting started.

“He never ran for public office. He never held another appointed state government position, but was always very involved in the operation of Illinois state government,” Michaelson said.

Michaelson says since Cellini’s indictment three years ago, he has not gone into hiding, and is still active with the Illinois Asphalt Pavement Association.

In his career, state contacts helped the Cellini, a Springfield Republican, earn tens of millions from real estate, casino and even asphalt businesses, and he’s held on to much of his wealth.

CBS 2 Legal Analyst Irv Miller said this could prove money has more influence than political loyalty.

“He is one of those guys the government believes is behind the scenes, basically making a ton of money on this pay-to-play politics,” Miller said. “He’s the one that’s making the money. He is the one who is getting campaign contributions in exchange for the money. He’s the one that’s basically influencing politicians like Blagojevich in the scheme of government, and that’s why he is on trial.”

The son of a policeman, Cellini also has a reputation as savvy and meticulous and a man not to be crossed.

“He was so well connected, if he was upset with you, there was a perception he could make a few calls — and you may not get that state job or state contract you wanted,” said David Morrison, deputy director of the Illinois Campaign for Political Reform.

The trial will offer another peek at the underbelly of Illinois’ scandal-plagued politics. To lay the groundwork for their claim that Cellini conspired to shake down movie producer Thomas Rosenberg, prosecutors plan to show he forged ties with top-tier politicians as far back as the 1960s. Their success, however, could depend on whether jurors believe a single witness tainted by his own association with Blagojevich.

The defense objected in pretrial hearings that prosecutors were trying to cast Cellini’s knack for befriending the powerful in a sinister light.

“Those things are not illegal. But the government wants to offer those things to muddy and dirty up Cellini,” said defense attorney Dan Webb, a former U.S. attorney who also defended Blagojevich’s predecessor, Republican Gov. George Ryan, who is serving a 6 1/2 year term on multiple corruption counts at an Indiana prison.

While Blagojevich was charged with multiple crimes, Cellini is accused of a primary one: That he and three others tried to squeeze Rosenberg for a $1.5 million donation in 2004. Cellini has pleaded not guilty to extortion conspiracy, attempted extortion, solicitation of a bribe and conspiracy to commit fraud and is free on $1 million bond. If convicted on all counts, he could spend more than 50 years in prison.

Prosecutors claim Cellini and his cohorts, including Blagojevich insiders Tony Rezko and Chris Kelly, planned to threaten Rosenberg’s investment company with the loss of $220 million in state pension money from the $30 billion Illinois Teachers Retirement System they controlled unless he made the donation.

Prosecutors say the conspirators badly misjudged one thing: Rosenberg himself.

Cellini’s job, prosecutors say, was to call Rosenberg and gently remind him he hadn’t contributed to Blagojevich even though his company had already received millions in teacher pension funds. Others were to turn the screw in follow-up calls.

Cellini agreed to the plan to fulfill an earlier promise to steer big-time contributors to Rezko and Kelly in exchange for them making sure he kept his profitable contacts under the Democrat-led administration.

Rosenberg, however, bristled when Cellini conveyed the message. The producer told Cellini he thought Rezko and Kelly were trying to squeeze him, and according to court documents filed by prosecutors, he warned Cellini, “You know, by God, I’ll take `em down. … I resent these strong-arm guys.”

As the conspirators backed away from Rosenberg in fear he’d blow the whistle, an increasingly nervous Cellini bemoaned Rezko and Kelly’s lack of caution in a conversation with the fourth member of the group, prominent state board member Stuart Levine, according to FBI wiretaps.

“I know that their (modus) operandi is different than what ours was,” Cellini said. “We would not call somebody after they got something or before they were gonna get something.”

But when Levine asked Cellini if he was willing to cut all ties with the two, Cellini paused and then said: “Phew, you know neither one of us want to do that.”

The defense claims Cellini’s words were taken out of context and actually show he disapproved of Kelly and Rezko’s behavior.

Which side the jury believes will likely hinge on the testimony of prosecutors’ star witness — Levine.

But Cellini’s attorneys are sure to question Levine’s credibility. He created a sensation at Rezko’s trial when he admitted snorting cocaine — sometimes at marathon drug parties.

“If the jury finds he’s credible, Cellini is in big trouble,” Morrison said. “If they don’t, Cellini’s probably not going to prison.”

Kelly committed suicide in 2009, just days before he was to report to prison on an unrelated conviction.

Prosecutors haven’t said whether Rezko will testify at Cellini’s trial. Ironically, he was convicted on multiple charges in 2008 but acquitted of the specific charge of trying to squeeze Rosenberg for cash — suggesting Cellini’s conviction is far from a foregone conclusion.

(TM and © Copyright 2011 CBS Radio Inc. and its relevant subsidiaries. CBS Radio and EYE Logo TM and Copyright 2011 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed. The Associated Press contributed to this report.)

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