Excerpt - Ice and snowstorms have closed Iowa's airports and highways in recent days, stopping even the most determined presidential candidates in their campaign tracks. But Thursday, caucus night here, the weather may be more than an annoyance. Political analysts say the atmospheric conditions could have a serious impact on how candidates fare in this first step in the nation's presidential nomination process. Right now, meteorologists are expecting a balmy (by Midwestern standards) high of 41 degrees, sunny conditions and a 10% chance of precipitation. That forecast suits Hillary Clinton on the Democratic side, and Mitt Romney on the Republican...