Intrade.com The political futures trade in a price range from zero to 100. For example, as of this writing, the contract on Barack Obama being the Democratic nominee is trading at about 57. After the Democratic National Convention in August, if it turns out that Obama is the nominee, the contract will be pegged at its maximum value of 100 -- so if you bought it at 57, you'd have a profit of 43, for a return of about 75% for an investment of six months. But if Obama is not the nominee, the contract will get pegged at zero, and you'll lose your entire investment of 57. Before the convention while the contract is still trading, you can buy it and sell it at any time, taking little profits or losses along the way just like you could with any futures contract. And if at any point you wanted to bet that Obama would not be the nominee, you could sell the contract short. Just like soy beans or pork bellies. These markets have been around for several election cycles now, and they have proven generally to be more accurate than traditional opinion polls. In fact, before modern scientific polling was even invented in the 1940s, betting markets this like used to exist on the nation's stock exchanges, and their results were reported every day in the newspapers just like poll results are today. Their long-term record of accurate prediction was astonishingly good. There are Intrade.com markets on all the candidates (and on thousands of other political and world events, as well). For example, the contract on Hillary Clinton being nominated is now trading around 43. Note that Obama price of 57 and the Clinton price of 43 add up to 100. That's because at this point it's pretty obvious that one of them is going to be the nominee. Now here's where it gets interesting, and useful for stock investors. Since the Obama and Clinton contracts add up to 100, the price of either one of the contracts can be interpreted as the percentage probability that that candidate will get the nomination. In other words, today Obama has a 57% probability while Clinton has a 43% probability. So to see how the stock market "likes" or "dislikes" any particular candidate, all we have to do is make a comparison of the way the stock market moves in relation to the Intrade.com contracts.