But why is Illinois so much more prone to this sort of thing than neighbours such as Iowa, Wisconsin and Missouri?
Part of the explanation is statewide. By American standards, Illinois has weak disclosure and conflict-of-interest laws, and a fragmented governing structure of close to 7000 separate administrative units - from state to city to county and an even more local level - makes it easy for pockets of graft to develop and flourish undetected.
Whether or not Illinois is the most corrupt of the 50 American states is a matter of dispute. By one estimate, corruption - in the shape of scandals, bloated payrolls and padded contracts - costs Illinois taxpayers US$500 million ($647.6 million) a year. And this in a state facing a budget crisis exceeded only by California, and a fiscal shortfall next year of US$17 billion.
But this culture was not born in Springfield, the sleepy state capital where the Illinois legislature is to be found and governors are supposed to spend most of their time.
These days Springfield is above all a museum, celebrating its most famous son, a 19th century lawyer and one-time state legislator named Abraham Lincoln. The real seat of the action lies a three-hour drive to the northeast on Interstate 55.
Chicago is one of America's, indeed the world's, great cities, in its magnificent setting on Lake Michigan's shore. The skyscraper was invented there, it was long America's mercantile and transport hub, a seat of industry and hard work.
Chicago may not be the state capital, but it utterly dominates Illinois, accounting for half the state's population and half its Congressional seats in Washington. Inevitably, it has set the state's political style.
That style grew from the city's explosive growth, from a swampy village of a few hundred souls in the 1830s into an urban centre of 120,000 by the time Lincoln was elected President in 1860.
Those who ran the place, supervising this expansion, wielded huge power. Thus was born an alliance between venal city government and organised crime, resulting in the notorious "Outfit" of the early 1900s that would later produce Al Capone.
The Mayor in Capone's day was "Big Bill" Thompson, derided even then by the local press for making Chicago an international laughing stock, famous for its "moronic buffoonery" and "unchecked graft".
All the while there developed the Chicago "machine", trading public jobs, contracts and other services for votes and political support.
The Windy City may not have invented the practice, but few raised it to a higher art form than Chicago's mayors, not least the Richard Daleys, father and son, who between them led the city for the best part of half a century.
In Chicago, power has historically been wielded like a club - often in pursuit of money. Mike Royko, the late and legendary Chicago Sun-Times columnist proposed a new city motto, "ubi est mea", or "where's mine?"
But secretly, one suspects, Chicagoans relish their bad-boy reputation. Outwardly they may cringe at the fact that, despite Barack Obama, Michael Jordan and Oprah Winfrey, their most famous citizen of the 20th century remains Capone.
Yet Blagojevich - whose most famous offence was the attempted sale of the Senate seat vacated by then President-elect Obama - was treated like a wayward rock star.
And Chicago has exported its methods far beyond Lake Michigan. It was Archbishop Paul Marcinkus, a priest in Cicero on the city's tough west side before moving to Rome, who led the Vatican's bank, the IOR, into financial scandal and near ruin in the early 1980s.
Closer to home was Congressman Dan Rostenkowski, who as chairman of the House of Representatives was Chicago's most powerful politician in Washington before Obama.
But in 1994 "Rosty" was caught using Congressional cash to buy presents for friends and padding his Washington payroll with fake jobs.
He went to jail, but even ex-President Gerald Ford was among his sympathisers.
"Danny's problem was that he played by the rules of the city of Chicago," Ford wrote later. "They aren't the same rules as every other place in the country lives by, but in Chicago they were totally legal and Danny got a screwing."
Rostenkowski spent just 15 months behind bars, compared with the 14 years meted out to Blagojevich, one of the stiffest punishments for political corruption on record.
It is intended as an example. But this Illinois scandal is unlikely to be the last.
- Independent
