From here. This chart is the usual VoteView scatter plot with one more bit of data added.  For those who haven’t been following along each point is a member of congress, and the X axis shows how economically conservative the member is (e.g. how much they prefer legislation that servers large economic entities v.s. small ones); and the vertical economic axis is their preferences on civil rights issues, higher is (roughly) more socially liberal.  The red points are the Republicans and the Democrats are blue.  As you can see there are few, if any centrists, and the two parties are totally polarized.

The added datum is the “grade level.”  It’s based on a somewhat silly measurement tool that used on text to estimate the grade in school the reader would need to have achieved to read that text.  In this case the text is the member’s statements in the congressional record.

Honestly I don’t know that I’d draw any conclusions from this, but don’t let me stop you from that pleasure.