Originally posted on 10/13/2012:

@ Justin7
There's 4587 shares to be bought on Obama at $6 +/- 4 cents, so roughly 4587*6 = $27522. This isn't counting the roughly parallel markets of Romney to win and the Democratic party to win the presidential election. Can pinnacle bettors have a maximum open position of 10k or may bettors re-bet? Alternatively, could you consider all internet sportsbooks offering the market at similar odds an aggregated 'market', where it may be possible to bet more than at Intrade?

I was considering buying Obama on Intrade as a 'good' play, as so many sportsbooks have him at shorter odds. Perhaps the discrepancy is due to Intrade accepting US customers, while many sporsbooks don't. Obama has a way higher approval rating outside of the USA than Romney, so maybe there is a bias towards what traders subjectively want to happen in geographically disparate markets, or bias in the perceived likelihood of the candidate winning (e.g. Europeans' high approval of Obama translating into the belief that he is likely to win, subconsciously discounting the prevalence of Conservative opinion in America).

@Heehawwww
I can't find any significant rule differences, however pinnacle's market is for which party will win the election while Intrade offers both party and candidate markets, so barring the replacement of a candidate (surely a miniscule probability), the markets are effectively the same.