Not so fast, Illinois. Lots of states can claim the title of America's Most Corrupt.

At or near the top of some lists is Louisiana, certainly no slouch in the derby of the dirtiest. But any state's fitness for the throne of political turpitude depends on the criteria used to define "corrupt."

There are several methods of quantifying corruption. Each of them tries to home in on states that outslime others.

By USA Today's tabulations, factoring in convictions with the populations of all 50 states, the crown goes to that Sodom of the Snow Belt — North Dakota?

Experts scoff at the newspaper's mathematical assessment that Illinois musters no better than 18th on the dishonor roll, sex scandals not included. A state's population can skew everything.

Rod Blagojevich started this argument.

The Illinois governor was accused of offering an open U.S. Senate seat to the top bidder, making him eligible to be the fourth of the last eight Illinois governors to have trouble with the law. And an FBI supervisor in Chicago said, "If it isn't the most corrupt state in the United States, it's one hell of a competitor."

Turns out the competition is intense — except, perhaps, within the triumvirate of vanilla do-rights known as Kansas, Nebraska and Iowa.

Missouri, on the other hand, seems to own the mushy middle. You know, a state attorney general here, a House speaker there ...

Web sites now sponsoring online surveys on the topic confirm what experts have sensed all along: that citizens tend to argue that their own state officials are the worst.

Florida wins ... maybe

"It's notoriously difficult to measure political corruption," said Christopher Z. Mooney, a professor of political studies at (ahem) the University of Illinois at Springfield. "It's a very rare behavior. You can neither ask people about it nor observe it."

If you total up the raw numbers for federal convictions of public officials since 1998, as The New York Times did last week using U.S. Justice Department data, Florida wins by a crooked mile.

But Florida's population is 18 million and booming. High-population states with lots of public employees have a natural edge in the ignominy index over smaller states with fewer public officials, said Russell Mokhiber, editor of Corporate Crime Reporter.

In 2004, "when we were the first to slice it and dice it," Mokhiber published federal corruption convictions over a six-year period per capita, dividing political skullduggery by population.

He quickly learned a lesson when North Dakota topped his charts, too. Mokhiber ever since has left the 15 most thinly populated states out of the running, because a relatively modest sweep of arrests can drive them way up the corruption charts.

North Dakotans had not seen a statewide official thrown behind bars in decades.

Bad rap for North Dakota?

Corrupting the Justice Department's database, however, was a statistical anomaly: Prosecutors in a single year, 2003, wrapped up a rash of embezzling cases mostly involving Native Americans on North Dakota reservations. Sixteen federal convictions that year were about four times the state's annual average, enough to carry with it the "most corrupt per capita" distinction still.

Are conviction rates a fair measure in the first place?

"Convictions only point to the aggressiveness of a prosecutor," said Don Morrison of the watchdog group North Dakota Center for the Public Good. "In places that are truly corrupt, offenses don't get taken to court. They don't even get reported."

Some analysts look to states deemed to have weak laws regarding campaign finance, ethics and disclosure. On that score, a study this year awarded the booby prize to ... uh-oh, South Dakota.

Others put stock in polls that attempt to gauge a citizenry's tolerance of corruption. If the people shrug off backroom deals and graft, so will their elected leaders, giving rise to "a culture of corruption."

"Getting a read on that culture, that to me is the strongest of the prongs," said Jay Stewart of the Better Government Association, based in Chicago.

Like Illinois, Louisiana still has a governor in prison — and a U.S. House member probably headed that way. Alabama's governor got out, but the mayor of Birmingham, just arrested on bribery charges, may be headed in. New Jersey is, well, New Jersey, where some think the state motto should be: "You wearing a wire?"