In terms of ancestry, 24.3% were German, 13.0% were Irish, 7.9% were Polish, 7.4% were Italian, 7.1% were English, and 2.4% were American.

During the years that the county was represented by Dennis Hastert it received many federal earmarks for highway improvements to respond to population growth.

Kane County services are overseen by a 24 member Board which is elected every two years.

In addition to the Board chair, there are nine county officeholders elected countywide every four years.

The fourth subcircuit consists the tri-cities area of Batavia, Geneva, and Saint Charles.

Kane County then unsurprisingly became solidly Republican for the century and a half following that party's formation.

It voted for the GOP presidential nominee in every election between 1856 and 2004 except that of 1912 when the Republican Party was mortally divided and Progressive candidate Theodore Roosevelt carried the county with a majority of the vote over conservative incumbent William Howard Taft.

The gradual shift of the GOP towards white Southern Evangelicals, however, has led the generally moderate electorate of Kane and the other "collar counties" to trend towards the Democratic Party.

In 2008, Senator Barack Obama became the first Democrat to carry Kane County since Franklin Pierce in 1852, and the first ever to win an absolute majority of the county's vote (the previous two Democratic winners, Pierce and James K. Polk in 1844 had both gained only pluralities due to strong Free Soil votes).