The hottest Republican presidential candidate in the Iowa market this week has been RCROF, which stands for "Republican Convention Rest of Field"--i.e., none of the above. As of Wednesday, RCROF was trading at nearly 16 cents a share, its highest value in more than a month. RCROF's surge coincides with John McCain's campaign kickoff and a selloff of stock in Elizabeth Dole and Steve Forbes. These trends suggest that many investors are treating RCROF as stock in McCain and are betting on him as the Republican alternative in case George W. Bush stumbles.