Impeached Illinois Gov. Rod Blagojevich was sentenced Wednesday to 14 years in prison for 18 corruption offenses, including an attempt to sell the U.S. Senate seat vacated by Barack Obama when he became president.

Blagojevich, who turns 55 on Saturday, will have to serve at least 12 years behind bars, under federal regulations.

Addressing the court before U.S. District Judge James Zagel pronounced sentence, Blagojevich apologized, his first public manifestation of remorse since he was arrested in December 2008.

"The jury decided I was guilty. I am accepting of it. I acknowledge it," the disgraced politician said. "I never set out to break the law. I never set out to cross lines. I have nobody to blame but myself for my stupidity and actions and the things I did and I thought I could do."

Blagojevich, a Democrat, stepped down in January 2009 after the Illinois legislature impeached him.

Federal officials, who had been investigating Blagojevich for some time, decided to arrest him in December 2008 when they learned he was seeking to obtain an appointment in Washington or campaign contributions in return for Obama's vacant Senate seat.

Blagojevich is the second consecutive former Illinois governor to be sentenced to prison for corruption. His Republican predecessor, George Ryan, was convicted in 2006 and is serving a sentence of 6 1/2 years.