The latest Des Moines Register poll highlights some noteworthy Iowa-caucus trends. Among them: Edwards has declined in Iowa; Clinton's lead is real, but not unstoppable; and the Giuliani-McCain trend in Iowa is downward, while the Thompson-Huckabee trend is upward. But here is the most salient fact: Among likely caucus-goers, only one-fourth of respondents said their minds were all made up. Which means three fourths could be persuaded to change their decisions before January 3, 2008. You can expect plenty of volatility in the months ahead.