Two states, Maine and Vermont, allow prisoners the vote. Every other state and the District of Columbia all restrict felons' voting rights to some degree, and two states, Kentucky and Virginia, deny voting rights for life to anybody with a felony conviction and never mind whether they've paid their debt to society--they still have to pay, and can never have a vote again. This is draconian. Alaska is on the more restrictive end of the spectrum, although not in with the most restrictive states. Overall, the US has the highest incarceration rate in the world (although perhaps China may be higher--it's hard to tell).
SB 68 is a bill that should be passed. The Sentencing Project has some interesting statistics on incarceration and felony disenfranchisement (although, curiously, it doesn't provide statistics for Alaska Natives). There's a somewhat old site specifically on Alaska's prisoners that claims (as of November 2006) that "Alaska has one of the highest incarceration rates in the country." SitNews reported this February that
the number of inmates in Alaska's prisons will likely double by 2030 unless the state significantly increases its prevention, intervention, education and treatment programs soon…. The study showed that Alaska's prison population is among the fastest growing in the US, with 5 times more inmates in 2007 than in 1981.It's expensive, too.
ISER's research summary is here. (PDF)