Two rich Democrats were friends. Now they are spending millions to attack each other. The Washington PostThe most costly primaries you’ve never heard of are raging on D.C.’s doorstep Axios‘What a frickin’ waste’: Inside the plutocrat feud for a Maryland congressional seat MS NOWThe $32 million primary: Trone, McClain-Delaney clash in Maryland race WUSA9Maryland Congressional 6th District primary election results The Herald-Mail