Visitors to the nation's third-largest city are usually spotted wandering the Magnificent Mile, snapping pictures of the Willis Tower and sampling Chicago-style deep dish pizza, but if some persistent Illinois lawmakers and Mayor Rahm Emanuel get their way, a glitzy casino would be on their agenda, too.

Trying to land a Chicago casino has become an annual sticking point, despite political gusto from mayors and legislators who want to expand gambling in Illinois. Gov. Pat Quinn has axed two gambling bills and invoked images of infiltrating "mobsters." Along that same theme, the head of the Illinois Gaming Board said the pending plan is inherently problematic because of the way a Chicago casino will be managed.

Still, the latest bill — which recently cleared the Illinois Senate and also would allow slot machines located in lounges at O'Hare and Midway — appears to have the best chance yet.

For the first time, Quinn signaled his support for gaming in a major speech, saying this year that he'd be open to a gaming bill if the revenue benefits schools, a stance that comes as Illinois faces mountainous money problems.

Meanwhile, Emanuel is pushing hard for the proposal, lawmakers are eager to rework it and business leaders would love the chance to plant a casino in Chicago — the largest American city to date — with thousands of noisy slots, an entertainment venue and a continuous flow of money-spending tourists.

"It's not just another riverboat casino, it has the potential to be a destination in its own right," said Jack Johnson, head of the Chicago Convention & Tourism Bureau. "Anytime you can add another destination to Chicago, it's one more reason to come."

The bill calls for five new Illinois casinos, including one in Chicago, and airport slots. If airports want them, Chicago would be unique among U.S. airports outside Las Vegas. The plan would establish a Chicago Casino Development Authority, a board of mayoral appointees. The Illinois Gaming Board would have regulatory oversight, but most everything else, including contracts and day-to-day operations, falls to the city board.

And there's the potential rub.

Some experts raised concerns at the Chicago setup when compared with urban casinos — in Philadelphia, Detroit and New Orleans — where the state board oversees everything.

"That is a rare situation," said Doug Walker, an economics professor at the College of Charleston. "Anytime you have a new group of regulators, there's another potential area for corruption."

That very issue prompted state gaming board head Aaron Jaffe to question why Chicago needed its own board and resulted in a spat with lawmakers during a hearing on the bill last month. That followed similar questions from Quinn, who vetoed gambling bills over lack of ethical standards. It's a theme he often brings up in a state where four of the last seven governors have gone to prison, including his predecessor Rod Blagojevich.

Even opponents who typically raise concerns about potential social costs — including increases in problem gambling — are also talking about ethical concerns. Partly that's because it's not hard to find corruption headlines in a city that's been under a court order to root out political patronage or where federal data shows more than 1,500 public corruption convictions since the mid-1970s.