Not as impressive as nearly winning a competitive race against an incumbent to be honest. Generally in seats where the opposing party wins by +10-+20 competent people won't run because they (correctly) realize they have no chance in the general election, leading to the primaries of the perennially losing party to be a who's who of crazy nutjobs. It's why you occasionally see the bait articles on "legitimate neo-nazi wins primary race!" because they were running unopposed in a district where the other team wins by 50 points.