here is the bet to make on intrade.com
short obama, long any dem at 60 long mccain, guilliani, huckabee and romney for total cost of 39..
make 61 if one of four repubs win +43 on obama short lose 60 on any dem total gain 44
if dem besides obama wins..40 on dem trade + 43 on obama short total gain 44
obama wins make 40 on any dem, lose 43 on short + 39 on repubs total loss 42
two out of three win..only an obama victory is losing trade