Chicago ? Corruption charges against Illinois Gov. Rod Blagojevich focus on much more than the claim that he tried to sell or trade Barack Obama’s U.S. Senate seat.

That charge could be just gravy to prosecutors. But the meat and potatoes are buried deep within a 76-page affidavit tacked onto the charges, and they have a familiar look.

Evidence of misuse of political clout, fixed contracts and illegal campaign fundraising — the basic staples of corruption in Illinois — proved persuasive with the jury at influence peddler Tony Rezko’s fraud trial. He was convicted and awaits sentencing.

That same evidence is now coming back to bite Blagojevich. This time around it could be even stronger because Rezko — the political fundraiser who helped to bankroll the campaigns of both Blagojevich and Obama — may take the stand to point the finger at the governor.

Rezko, for example, was on hand while Blagojevich talked to a campaign donor about putting him on the state payroll with the donor’s $25,000 check on the table, according to testimony at Rezko’s trial.

Blagojevich has been in the national spotlight since his Dec. 9 arrest, with a criminal complaint alleging he was caught on secretly recorded phone calls talking about money or favors he could get in return for his power to appoint someone to Obama’s seat. The seat remains vacant, and the Democrat-controlled legislature went home this past week without taking up a bill to have a special election to fill it.

The governor strongly proclaimed his innocence on Friday, telling reporters he is “not guilty of any criminal wrongdoing.” He did not take questions.

“I will fight, I will fight, I will fight until I take my last breath,” Blagojevich said. “I have done nothing wrong, and I’m not going to quit a job the people hired me to do because of false accusations and political lynch mob.”

His attorney, Ed Genson, spent the week shooting down the federal case, claiming the federal wiretaps used to capture his conversations were illegal and dismissing his discussions about the Senate seat as just talk.

“There’s no evidence that anyone ever asked anybody for anything with regard to that seat,” Genson said as a legislative impeachment panel began considering whether to try to remove Blagojevich from office.

Legal experts such as Professor Leonard L. Cavise of DePaul University say federal prosecutors may have a long way to go before they have all the evidence they need that Blagojevich tried to trade or sell the Senate seat. But some say the tale of corruption coming from the witness stand at Rezko’s trial is much firmer.

“All that stuff has been investigated for years, all that stuff is pretty much tried and true,” says Cavise.

Blagojevich, 52, was arrested by FBI agents and charged with conspiracy to commit fraud and solicitation to commit bribery.

The first charge alleges that he defrauded the people of Illinois of his honest services as governor. It ties together material from the Rezko trial and the allegations concerning the Senate seat.

The second charge alleges that he sought to use his economic power as governor to force the Chicago Tribune to fire editorial writers calling for his impeachment.