Hokkaido has an area, climate and population density very similar to Wisconsin. Most of the population is clustered in a few big cities on the south end, including Sapporo and Hakodate.
Sorry, I SHOULD have said the SOUTHERN half of Wisconsin. Overall, Wisconsin is about twice as large in area with a density of 40.6 per square km versus 63 in Hokkaido. But the SOUTHERN half and Hokkaido are similar with about 5.2 million residents each.
Roughly 600,000 people live in the NORTHERN half of Wisconsin.