WASHINGTON (CBS) — Former Gov. Rod Blagojevich has lost what appears to be his last bid to get his corruption convictions overturned, after the U.S. Supreme Court declined to hear his case Monday.

The high court did not offer an explanation for its decision, which was simply included on a list of cases it declined to hear, posted Monday on the court’s website.

Defense attorney Sam Adam Jr., who represented Blagojevich at his first trial, but left the defense team before the second trial and subsequent appeals, said the Supreme Court’s decision is not a surprise.

“I’m not surprised, but certainly disappointed. When the untimely and unfortunate death of Supreme Court Justice Scalia came out, I pretty much figured it then. He was the one that we thought very well may force this to go through,” he said.

Blagojevich, 59, has spent the past four years in a federal prison in Colorado, after he was sentenced to 14 years for 18 corruption convictions, following two trials. Among the charges against Blagojevich were allegations he tried to sell or trade an appointment to the vacant U.S. Senate seat once held by President Barack Obama, shortly after his election in 2008.

A federal appeals court later overturned five of Blagojevich’s 18 convictions, and ordered a new sentencing for the former governor if prosecutors decide not to retry him on those counts. U.S. District Judge James B. Zagel has yet to schedule any further hearings in the case, likely awaiting the Supreme Court’s decision.

While Blagojevich could get a reduced sentence at a new sentencing hearing, the 7th Circuit Court of Appeals noted the evidence against Blagojevich was “overwhelming,” and the 14-year sentence he received was not necessarily excessive for the 13 remaining convictions.

“It is not possible to call 168 months unlawfully high for Blagojevich’s crimes, but the district judge should consider on remand whether it is the most appropriate sentence,” the appeals court wrote last year.

Adam said he thinks Zagel will reduce Blagojevich’s sentence when the case comes up again in the trial court.

“This is a non-violent offense. Fourteen’s certainly too high, especially for a man who will end up in his 70s … and get out for a non-violent offense. I think there’s a big chance he could take some time off,” he said.

The former governor and his defense team have long proclaimed his innocence, arguing he was participating in legal political horse-trading, and claiming the line between legal and illegal trading of political favors has become blurred, possibly leaving every politician in the U.S. open to prosecution.