The numbers are very weird.
In the 2000 census there were 464,000 Alaskans over the age of 18.
In November 2010 there were 494,000 registered voters!!!
These numbers are approx; I had the links and lost them. Will try again.
http://www.elections.alaska.gov/results/10GENR/data/results.htm
The above link shows the registered voters as 494,876.
http://quickfacts.census.gov/qfd/states/02000.html
Population quick facts for July 1, 2009.