UPDATED: 3/16/2012 11:23 a.m.

CHICAGO (CBS)–The federal sentencing for the former chief of staff to disgraced former Gov. Rod Blagojevich was postponed on Friday.

The delay was due to a court scheduling conflict, and the sentencing is now scheduled for March 28 at 1:30 p.m.

Harris was supposed to be sentenced the day after Blagojevich began his 14-year prison sentence. Harris pleaded guilty to a single count of wire fraud. He faces a maximum sentence of 20 years behind bars.

Harris is seeking a sentence of only probation.

Harris was arrested the same day as Blagojevich on Dec. 9, 2008, when the feds accused him of scheming to sell or trade an appointment to the U.S. Senate. Unlike his boss, Harris resigned as chief of staff shortly after his arrest, began cooperating with federal investigators within days, and eventually became the star witness at Blagojevich’s two trials.

Last week, defense attorney Terry Ekl argued Harris should be sentenced to unsupervised probation in light of his guilty plea and cooperation with the feds.

Harris spent a total of 10 days on the witness stand at Blagojevich’s to trials, as the government’s chief witness against his former boss.

In arguing for a lenient sentence, Ekl claimed that Harris took a number of steps to try to deter Blagojevich’s misconduct, including telling the former governor he shouldn’t try to make a deal for a Senate appointment, that he refused to ask then-Illinois Senate President Emil Jones to give Blagojevich the money from his campaign fund in exchange for the Senate seat, and that he told Blagojevich he couldn’t accept campaign cash in exchange for appointing Congressman Jesse Jackson Jr. to the Senate.

After resigning from his job as Blagojevich’s aide, Harris took a job as an apprentice electrician working on high power lines.

Blagojevich began his 14-year sentence at the FCI Englewood federal prison in Littleton, Colo., on Thursday. He was convicted last year of 18 counts of corruption, including trying to sell President Barack Obama’s vacant Senate seat.

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