According to the latest Census Bureau estimates for the year 2012.
Other notable states:
South Dakota - 833,354
Montana - 1,005,141
Minnesota - 5,379,139
Wisconsin - 5,726,398
Wyoming - 576,412
Iowa - 3,074,186
Nebraska - 1,855,525
Population of the Dakotas - 1,532,982
Alaska is at 731,449. We may overtake them again.