The Edwards campaign has an interactive map that shows the Gore/Bush results and registers the changes if any state moves from the Republican column to the Democrat column. Most obviously if Edwards carried all Gore states plus his own North Carolina he'd carry the electoral college by 275 to 263. If Clark carried all Gore states plus Arkansas he's lose 266 to 272. Kerry and Dean don't change much as both their states voted Democrat in 2000. Of course, if so many minority voters had not been illegally disfranchised in 2000 then Gore would have won (butterfly ballot shambles or no) by 293 to 245.
I read the Iowa result as a nightmare for the Bush campaign both because they really want to run against Dean and because the sudden openness in the contest will keep media attention on Democrats at the expense of Bush.