Last week we examined how the Democratic presidential campaigns have performed in the context of Barack Obama's 2012 re-election.

That analysis grouped Obama's vote share into categories, highlighting how the country's reddest and bluest counties have voted for Hillary Clinton and Bernie Sanders so far in the Democratic primaries. Clinton, the clear frontrunner, performed best in areas where Obama was strongest against Mitt Romney. But Sanders did slightly better when majority black counties weren't factored.

Here's a look at the Democratic race (through the most-recent contests) in the context of voters' educational attainment. Each candidate's average vote share by county is grouped by the proportion of residents in those areas with at least a bachelor's degree. Sanders doesn't win among any group, but he generally performs best in places where voters have more education:

dems_edu