Major Important Election Question

I have noticed several states, where the race seems fairly close being “called” early in the evening. What bothers me is the percentage of precincts reporting.At 10:00p.m. central-Iowa is being called for Obama, less than 14% are reporting in that state.Minnesota is being called for Obama…25% of precincts are reporting and the spread is something like 52% 47% Obama.

How can states with less than half of the voters reporting, especially with the vote being so close be called?

Thanks…I shall now return to drowing my sorrows and planning my move to Cuba