Forget stocks, commodity futures or any of the usual stuff traded on the open market — how much is a presidential candidate like Mitt Romney or Hillary Clinton worth?

Believe it or not, there are political futures markets where wagers are being taken on presidential candidates, just as if they were pork bellies, soybeans, ethanol, precious metals or foreign currencies.

Through a number of Web sites, including one operated by the University of Iowa's business college, traders can place bets on, for example, who'll win the Republican or Democratic nomination next year.

Anyone can follow the several political future markets online, often through detailed graphs that show the ups and downs of each major candidate's value as determined by trading over time.

"It's kind of a fun thing to play with, and of course, it's the people who are political junkies who typically do," said Kirk Jowers, director of the University of Utah's Hinckley Institute of Politics.

While Jowers said he never actually plays the markets, he does keep an eye on them, sometimes sharing a candidate's ups and downs in trading as part of his classroom discussion on presidential politics.

"I am a big believer in finding all sorts of ways to make politics more interesting to students and the community. I think the markets do that," Jowers said. "People who are into stocks pay more attention because the format is something they understand."

Some Web sites, like www.newsfutures.com, use only "play money" so traders can't actually win or lose cash. But the University of Iowa and Intrade, a for-profit Web site based in Ireland, do require a financial investment to participate.

Presidential politics is just one category of trading at Intrade, which takes bets on just about anything, including the chances of Osama bin Laden being "captured or neutralized" or if CBS Evening News anchor Katie Couric will be gone by the end of the year.

University of Iowa finance professor Tom Rietz said in a recent telephone interview that the Iowa university's market was created for educational purposes — not to make money like the sometimes controversial Intrade.

"We're not profiting from this enterprise," Rietz said. "There's no bookies or anything like that."

He said what's been learned by studying the Iowa university's political futures market since its creation in 1988 is that the market has been more accurate than polling in predicting who would win the White House.