The Newsweek chart above from last fall shows the topics discussed at the debates for the two political parties, where they overlapped and where they didn't.
It's true this chart is a few months old, but we did that as a matter of decorum: no one needs to see "relationship of Donald Trump's fingers to the rest of his anatomy" on a Venn diagram.
If someone tells you there is no difference between the two political parties, show them this chart. Kim Davis. Really.