I have been following the Republican primary on Intrade, the betting market site. In the last few days, the probability Mitt Romney winning the nomination has gone down by about 10%, from about 80% to about 70%. The probability of Newt Gingrich winning the nomination has gone from virtually 0 to about 15% At the same time, the probability of President Obama being reelected has increased, from about 51% to about 56%. This is telling us something about the market’s perception of the relative strength of Romney versus Gingrich as a candidate.