DuPage vs. Lake IL

[King of Kensington]

What are the major differences between these counties?  

Both are quite affluent - DuPage is more so on the whole, but the wealthiest in Lake are wealthier than the wealthiest areas of DuPage.  In other words, DuPage is more consistently middle to upper middle class, while there is a much greater variation in Lake.

Lake has a significant Jewish population, DuPage has hardly any.  DuPage has a bit more of a  "white ethnic" Catholic population.  DuPage is more Republican than Lake.

Both are traditional centers of WASP Republicanism and Trump was a bad fit for both.

Are these perceptions correct?

[King of Kensington]

To what extent was Obama carrying DuPage in 2012 a "favorite son" effect? 

Trump was a bad fit for DuPage given that the GOP vote dropped by about 10 points.

[King of Kensington]

College graduates:

DuPage  46.7%
Lake  42.7%

Advanced degree:

DuPage  18.2%
Lake  17.2%

$100,000+ HH income:

Lake  38.8%
DuPage  38.1%

$200,000+ HH income:

Lake  12.2%
DuPage  10.6%

[King of Kensington]

Lake is less wealthy than I thought.  But then I realized that most of Chicago's tony North Shore suburbs are in Cook County.   

Most of Chicago's white ethnic groups moved westward when they suburbanized, right?  Except for Jews who started out on the West Side but moved northward. 

[King of Kensington]

DuPage has very very few Jews, even though in the first half of the 20th century the West Side was the main Jewish area of Chicago.  Why did they move north instead of further west as they suburbanized?  Were the western suburbs less welcoming to Jews than the northern suburbs?  Or did they shift over to the North Side prior to mass suburbanization?