I think that Obama has no reason to (do) worse in 2012 that he did in 2008. For the time being it seems that he could win these three states.
Obama has a very slight chance of being defeated in a re-election bid in 2012, and that would show that Americans grossly misjudged his abilities in 2008. The Republicans will have to win every one of Colorado, Virginia, Ohio, Florida, Indiana, and North Carolina that Obama won in 2008, and such states as Missouri (that Obama barely lost) and Arizona (that Obama would have won had the Republican nominee not been from Arizona).
Minnesota and Iowa are core Democratic States. Minnesota hasn't voted for the GOP nominee for President since 1972, and Iowa has voted for the Republican nominee for President (and then barely) since 1984. If someone had phrased the question as "more likely to lose", then the answer would be North Carolina, which Obama barely won in his landslide.
A competent and attentive incumbent President is unbeatable should he seek re-election. It is that simple.