Illinois is a Democratic stronghold in presidential elections and one of the "big three" Democratic strongholds alongside California and New York. It is one of the most Democratic states in the nation with all state executive offices and both state legislative branches held by Democrats. For most of its history, Illinois was widely considered to be a swing state, voting for the winner of all but two presidential elections in the 20th century. Political party strength in Illinois is highly dependent upon Cook County, and the state's reputation as a blue state rests upon the fact that over 40% of its population and political power is concentrated in Chicago, Cook County, and the Chicago metropolitan area. Outside of Chicago, the suburban collar counties continue trending Democratic while dow