PoliPundit spots a Washington Times article claiming that interstate migration patterns are helping increase the population of Republican-leaning states, thereby increasing their clout in the electoral college. He files it under the "demographics-are-bad-for-Democrats" department which is somewhat premature. The ensuing discussion among the site's commenters (revolving around the question of who is migrating, liberals to the conservative states or conservatives seeking ideologically friendlier climes) is worth reading, though as yet, no one's pointed out that the article PoliPundit linked was written by Donald Lambro who is notorious in Washington for being as overly upbeat on Republicans' chances as the New York Times is on Democrats'.
On November 6, 2000 (article not online), Lambro claimed that California was "clearly in play" in the presidential election the next day and stated that Oregon, Maine, and Iowa "were leaning toward Mr. Bush." Bush lost all three.
Demographics are important, no question, but good strategy, the issue climate and candidate effectiveness are more of a factor on elections in my opinion.