As the presidential election draws near, you might want to play with an interactive Electoral College map, such as this one from PBS.
It starts with the assumption that Kerry will win all the Gore States and Bush will keep his states. The Electoral Vote, however, would be 278-260 rather than 271-266 because of population growth in Bush's states.
If Kerry could win New Hampshire and Nevada, and everything else remains the same, the Electoral College Vote would be 269-269.
I'd give that scenario about a 1 to 5% likelihood.